Hellow fellow Blenderheads!
A little about me:
I have never been a very active member of the Blender society. Most of the time I was watching the professionals making miracles and the beginners making mistakes, while I posted very few projects (however, started a lot, but many of them are still waiting to be finished) here. Actually, I think I read too much, and didn’t practice enough the theories… 
So, I wanted to share some things I learned from my intellectual journeys on the internet. It won’t be a real tutorial written by me. I will just point at different articles, tutorials and blogs, so you can prepare for the challenge of modeling the human body. (I know, everybody can use Google, but…)
First, where everybody should start is two thread about the theory of modeling, started by ‘SomeArtist’:
http://www.subdivisionmodeling.com/forums/showthread.php?t=482 - The Form
http://www.subdivisionmodeling.com/forums/showthread.php?t=907 - The Pole
Then the blog of ‘SomeArtist’, there are very practical advices for organic modeling:
http://3dwisdoms.blogspot.com/
A general 3D tutorial from 3DTotal, there are very nice pictures of the human anatomy, could be used as reference:
http://67.15.36.49/team/Tutorials/mahf/mahf_01.asp - ‘Modeling the Human Figure’ by Peter Ratner
Links of pictures and descriptions of the human proportions:
http://www.realcolorwheel.com/human.htm
And here is a .blend file of a roughly set up reference, to start with, plus a .zip containing some pictures and text:
http://www.hetenynet.hu/paradox/human_proportions.blend
http://www.hetenynet.hu/paradox/proportions.zip
I hope these will help at least the beginners.