[1] Marks Daily Apple (Website and forum a wealth of information)
[2] Nora Gedgautis Book Primal Body Primal Mind
[3] Robb Wolfs The Paleo Solution Book
[4] PaleoNu - A doctor who pushes a paleo style diet.
[1] http://www.marksdailyapple.com/primal-blueprint-101/
I totally agree to that. Those sources changed the way I was thinking about human health and nutrition completely. To be quite honest, I was not thinking about these topics very much before. I would also add a source that kind of got me started:
http://wholehealthsource.blogspot.com/
Stephan appears to be a very knowledgeable guy, he is probably the least "radical" in his approaches, writes on a variety of topics and is not afraid to change his opinions when faced with contradicting evidence.
Also, blog of Dr. Mike Eades http://www.proteinpower.com/drmike/ and Hyperlipid http://high-fat-nutrition.blogspot.com/