The list is for print & pdf products published since the year 2000 (approximately) for Gygax-era flavors of D&D: OD&D, Holmes Basic, AD&D, B/X, and BEMCI.

So nothing for 2nd edition AD&D or later editions. Clone/simulacrum systems and related products count, but only if they remain true enough to the actual Gygax-era flavors of D&D.

Castles & Crusades, for example, is not included. (But the Castle Zagyg products are included because of their strong thematic relevance to Gygax-era D&D.)

(There are fewer after Apr 2012 only because I stopped searching for them, except where various specific interests took me.)

https://princeofnothingblogs.wordpress.com/2021/02/07/palace-of-unquiet-repose-now-for-sale/

see info link
probably was available to Kickstarter backers on Jan 21 https://www.kickstarter.com/projects/mercilessmerchants/the-palace-of-unquiet-repose/posts

https://www.greyhawkgrognard.com/2020/12/11/d4-city-of-spiders-now-available/

http://beyondfomalhaut.blogspot.com/2020/11/module-baklin-jewel-of-seas-now.html

https://www.thebluebard.com/post/don-t-everyone-rush-at-once

https://beyondfomalhaut.blogspot.com/2020/08/stuff-gloomywood-one-afternoon-micro.html

https://www.drivethrurpg.com/product/317631/Darkness-at-Nekemte

https://www.knights-n-knaves.com/phpbb3/viewtopic.php?p=269761#p269761

http://justkeeponrollin.blogspot.com/2020/07/standalone-or-add-on-adventure-amongst.html

https://www.dragonsfoot.org/php4/archive.php?sectioninit=FE&fileid=497&watchfile=

https://www.dragonsfoot.org/forums/viewtopic.php?p=2092868#p2092868

https://beyondfomalhaut.blogspot.com/2020/07/module-in-shadow-of-city-god-trail-of.html

https://beyondfomalhaut.blogspot.com/2020/07/module-in-shadow-of-city-god-trail-of.html

https://www.dragonsfoot.org/php4/archive.php?sectioninit=FE&fileid=491&watchfile=

https://www.dragonsfoot.org/forums/viewtopic.php?p=2075668#p2075668

http://beyondfomalhaut.blogspot.com/2020/05/zine-echoes-from-fomalhaut-07-now.html

https://www.dragonsfoot.org/php4/archive.php?sectioninit=FE&fileid=489&watchfile=

https://www.dragonsfoot.org/forums/viewtopic.php?p=2072665&sid=a3a6bec5ae486ab6cda25d4b52ebf3b0#p2072665

https://www.drivethrurpg.com/product/302841/Hoard-of-Delusion

https://knights-n-knaves.com/phpbb3/viewtopic.php?f=64&t=16368

https://www.greyhawkgrognard.com/2020/03/27/t5-beneath-the-temple-of-elemental-evil/

https://www.drivethrurpg.com/product/307323

https://www.knights-n-knaves.com/phpbb3/viewtopic.php?p=264981#p264981

https://www.drivethrurpg.com/product/307320

https://www.knights-n-knaves.com/phpbb3/viewtopic.php?p=264981#p264981

https://www.drivethrurpg.com/product/306502

http://www.tenfootpole.org/forum/index.php?threads/digest-format-whats-the-appeal.177/#post-2290

https://www.dragonsfoot.org/php4/archive.php?sectioninit=FE&fileid=483&watchfile=

https://www.dragonsfoot.org/forums/viewtopic.php?p=2059865&sid=2b8f5396296add0766565dde23a7226b#p2059865

https://froggodgames.com/product/the-lost-crypt/

https://odd74.proboards.com/thread/13936/conan-secrets-black-circle-available

https://hellebardegames.com/shop?olsPage=products%2Fthe-temple-of-the-sun

https://www.greyhawkgrognard.com/2020/01/24/new-castle-of-the-mad-archmage-expansion/

http://beyondfomalhaut.blogspot.com/2019/12/module-castle-xyntillan-now-available.html

https://www.amazon.com/dp/0578616572/ref=sr_1_1?qid=1575220941&refinements=p_27%3AEugene+Weigel&s=books&sr=1-1

https://www.knights-n-knaves.com/phpbb3/viewtopic.php?f=64&t=16223

https://www.kickstarter.com/projects/1806106772/hyperborea-otherworldly-tales/posts/2697991

https://www.kickstarter.com/projects/1806106772/hyperborea-otherworldly-tales/posts/2697991

https://www.dragonsfoot.org/php4/archive.php?sectioninit=FE&fileid=477&watchfile=

https://www.dragonsfoot.org/forums/viewtopic.php?p=2036378#p2036378

http://www.lulu.com/spotlight/worldofthorkhammer

https://www.dragonsfoot.org/forums/viewtopic.php?p=2034361#p2034361

http://beyondfomalhaut.blogspot.com/2019/09/zine-echoes-from-fomalhaut-06-now.html

https://www.drivethrurpg.com/product/288750/Saving-Throw-fundraiser-fanzine-for-James-D-Kramer

https://www.knights-n-knaves.com/phpbb3/viewtopic.php?f=64&t=16138

https://www.dragonsfoot.org/php4/archive.php?sectioninit=FE&fileid=475&watchfile=

https://www.dragonsfoot.org/forums/viewtopic.php?p=2030363#p2030363

https://www.thebluebard.com/post/final-dhoga-maps

https://www.knights-n-knaves.com/phpbb3/viewtopic.php?f=2&t=16113

http://beyondfomalhaut.blogspot.com/2019/08/blog-more-adventures-in-morthimion.html

https://www.brwgames.com/2019/08/11/adventures-great-and-glorious-now-available/

http://beyondfomalhaut.blogspot.com/2019/07/module-nocturnal-table-now-available.html

https://www.dragonsfoot.org/php4/archive.php?sectioninit=SG&fileid=469&watchfile=

https://www.dragonsfoot.org/forums/viewtopic.php?p=2018833#p2018833

https://www.dragonsfoot.org/php4/archive.php?sectioninit=SG&fileid=468&watchfile=

https://www.dragonsfoot.org/forums/viewtopic.php?p=2018832#p2018832

http://beyondfomalhaut.blogspot.com/2019/07/stuff-further-adventures-in-morthimion.html

https://throughultansdoor.bigcartel.com

http://maziriansgarden.blogspot.com/2019/07/through-ultans-door-issue-2-is-finally.html

http://www.knights-n-knaves.com/phpbb3/viewtopic.php?f=64&t=15883

http://www.knights-n-knaves.com/phpbb3/viewtopic.php?f=64&t=15883

http://www.chaotichenchmen.com/p/f4-withered-crag.html

http://www.chaotichenchmen.com/2019/06/the-withered-crag-available-now.html

https://www.drivethrurpg.com/product/265629/Gunderholfen

https://www.dragonsfoot.org/forums/viewtopic.php?p=2011971#p2011971

http://savevsdragon.blogspot.com/2019/05/dragon-horde-zine-vol-2-issue-1-wherein.html

https://www.dragonsfoot.org/php4/archive.php?sectioninit=FE&fileid=467&watchfile=

https://www.dragonsfoot.org/forums/viewtopic.php?p=2009108#p2009108

http://josephbrowning.blogspot.com

http://josephbrowning.blogspot.com

http://josephbrowning.blogspot.com

https://www.dragonsfoot.org/php4/archive.php?sectioninit=SG&fileid=466&watchfile=

https://www.dragonsfoot.org/forums/viewtopic.php?p=2003559#p2003559

http://beyondfomalhaut.blogspot.com/2019/04/zine-echoes-from-fomalhaut-05-lost.html

http://beyondfomalhaut.blogspot.com/2019/04/zine-echoes-from-fomalhaut-05-lost.html

http://beyondfomalhaut.blogspot.com/2019/04/stuff-dungeons-of-morthimion.html

https://www.thebluebard.com/blog-1/zjelwyin-fall-release-day

https://www.dragonsfoot.org/php4/archive.php?sectioninit=FE&fileid=463&watchfile=

https://www.dragonsfoot.org/forums/viewtopic.php?p=1993203#p1993203

https://www.rpgnow.com/product/265544

https://www.kickstarter.com/projects/1806106772/hyperborea-players-manual-referees-screen-and-more/posts/2406716

http://www.hyperborea.tv/store/c1/Featured_Products.html

https://www.kickstarter.com/projects/1806106772/hyperborea-players-manual-referees-screen-and-more/posts/2406716

http://www.hyperborea.tv/store/c1/Featured_Products.html

https://www.kickstarter.com/projects/1806106772/hyperborea-players-manual-referees-screen-and-more/posts/2406716

http://www.hyperborea.tv/store/c1/Featured_Products.html

https://www.kickstarter.com/projects/1806106772/hyperborea-players-manual-referees-screen-and-more/posts/2406716

http://beyondfomalhaut.blogspot.com/2019/01/zine-echoes-from-fomalhaut-04-now.html

https://www.dragonsfoot.org/ft/index.shtml#460

https://www.dragonsfoot.org/forums/viewtopic.php?f=11&t=81366

http://savevsdragon.blogspot.com/2018/12/d30-pdf-download-d30-rat-generator.html

https://dreamscapedesign.net/2018/11/24/referee-repository/

https://www.brwgames.com/2018/10/26/now-available-the-tomb-of-harven-half-skull/

https://www.rpgnow.com/product/257155/What-Ho-Frog-Demons--HC04

https://www.kickstarter.com/projects/804120043/slumbering-ursine-dunes/posts/2325901?ref=backer_project_update

https://www.amazon.com/Dungeons-Dragons-Arcana-Special-Ephemera/dp/0399582754/ref=sr_1_1?ie=UTF8&qid=1540610594&sr=8-1&keywords=art+and+arcana

https://throughultansdoor.bigcartel.com

http://maziriansgarden.blogspot.com/2018/10/at-long-last-through-ultans-door-issue-1.html

http://beyondfomalhaut.blogspot.com/2018/09/zine-echoes-from-fomalhaut-03.html

http://savevsdragon.blogspot.com/2018/09/where-in-infinite-layers-of-abyss-have.html

http://savevsdragon.blogspot.com/2018/09/where-in-infinite-layers-of-abyss-have.html

http://savevsdragon.blogspot.com/2018/09/where-in-infinite-layers-of-abyss-have.html

http://www.hyperborea.tv/products.html

https://www.kickstarter.com/projects/1806106772/hyperborea-beasts-and-cannibals/posts/2251008

http://www.hyperborea.tv/products.html

https://www.kickstarter.com/projects/1806106772/hyperborea-beasts-and-cannibals/posts/2251008

http://www.drivethrurpg.com/product/245450

http://3toadstools.blogspot.com/2018/06/the-return-of-blue-baron-is-live.html

http://beyondfomalhaut.blogspot.com/2018/06/zine-echoes-from-fomalhaut-02-now.html

http://savevsdragon.blogspot.com/2018/06/d30-pdf-download-d30-minotaur-variations.html

http://www.greyhawkgrognard.com/2018/06/09/g1a-steading-of-the-hill-giant-chief-lower-caverns/

http://savevsdragon.blogspot.com/2018/09/where-in-infinite-layers-of-abyss-have.html

http://www.lulu.com/shop/rc-pinnell/fane-of-the-firebolg-queen/ebook/product-23641865.html

http://odd74.proboards.com/thread/12959/another-giant-adventure

http://beyondfomalhaut.blogspot.com/2018/05/module-barbarian-king.html

https://www.anthonyhuso.net/products-1

https://plus.google.com/+AnthonyHuso/posts/PaiZ4CvLg33

https://www.drivethrurpg.com/product/240765

https://www.kickstarter.com/projects/brwgames/castle-of-the-mad-archmage-musicland/posts/2174040

http://josephbrowning.blogspot.com/2018/04/malevolent-and-benign-ii-now-available.html

http://josephbrowning.blogspot.com/2018/04/advanced-adventures-compendium-four-now.html

http://www.lulu.com/spotlight/worldofthorkhammer

https://www.dragonsfoot.org/forums/viewtopic.php?p=1926221#p1926221

https://www.dragonsfoot.org/php4/archive.php?sectioninit=CD&fileid=439&watchfile=

https://www.dragonsfoot.org/forums/viewtopic.php?p=1923212#p1923212

http://beyondfomalhaut.blogspot.hu/2018/03/zine-shop.html

http://beyondfomalhaut.blogspot.com/2018/03/zine-echoes-from-fomalhaut-01-now.html

https://www.dragonsfoot.org/php4/archive.php?sectioninit=FE&fileid=438&watchfile=

https://www.dragonsfoot.org/forums/viewtopic.php?p=1919716#p1919716

https://www.dragonsfoot.org/php4/archive.php?sectioninit=FE&fileid=437&watchfile=

https://www.dragonsfoot.org/forums/viewtopic.php?p=1919371#p1919371

http://josephbrowning.blogspot.com/2018/03/advanced-adventure-40-horror-of.html

https://www.dragonsfoot.org/php4/archive.php?sectioninit=FE&fileid=436&watchfile=

https://www.dragonsfoot.org/forums/viewtopic.php?p=1916058#p1916058

www.rpgnow.com/product/234162/Wormskin-Issue-8

https://plus.google.com/+GavinNorman/posts/Pmf9HaVtH1M

https://beyondfomalhaut.blogspot.hu/2018/02/zine-echoes-from-fomalhaut-announcement.html

http://josephbrowning.blogspot.com/2018/02/advanced-adventures-39-dark-tower-of.html