Background
The Jesus Myth theory stands on 3 legs:
(i) Jesus is not known in early and authentic non-Christian texts;
(ii) Paul in authentic writings does not know of a historical Jesus, but only a spiritual figure known from revelation and cryptic interpretation of scripture;
(iii) the Gospels are not history but allegory and pastiche drawing on the Old Testament.
The biggest hitters in this area at the moment are Earl Doherty, Richard Carrier and Robert M. Price.
Edit: as of June 2014, Richard Carrier’s new book, the first ever peer-reviewed, university press-published argument for a mythical Jesus, is the definitive analysis of the whole issue, and to my mind proves the theory. Short essay summarising his case.
The Jesus Seminar was a major academic project to try to identify authentic Jesus traditions.
The Two-Source Hypothesis is one of two main theories of how the three synoptic Gospels are textually related, and probably the most popular. I prefer the Farrer Hypothesis.
The Jesus Myth theory
Richard Carrier's review of Earl Doherty's book
Introduction to Earl Doherty's theory
Main articles explaining Earl's theory
Second edition of Earl's book (a simply amazing book!)
Robert Price on the OT sources of the Gospels and extended book discussion
History of Mythicism and attempts at refutation
Earl's response to Bart Ehrman's recent book defending the Historical Jesus
Richard Carrier’s new and definitive book
Useful
A clever graph showing how late the narrative details of the Jesus traditions developed in the sources excluding the (fictive and little known!) Gospels
New Testament with interlinear Greek text
Also interesting
Richard Carrier on why Christianity is false
Carrier on why Christianity succeeded
Carrier on the formation of the NT canon
Vridar - the best amateur blog on NT reliability and Mythicism topics
My favourite series of articles proving the reattribution of Ignatius' letters to Peregrinus
A curious and enthralling series of articles arguing that the original author of the Pauline epistles was the arch-heretic, Simon Magus.
Robert Price’s book on the historical Paul, again theorised to be Simon Magus.
A critical commentary line by line on the sources and composition of the whole of Mark's Gospel