Well, I don't know of any sites, but I do know of a book. Bridgman has some anatomy books that are pretty good. His style is pretty, well, stylized, and he makes things a bit..."blocky"?, but it still helps. =] I found a preview of the book "Heads, features, and faces" on Google Book Search so you'll have an idea of his style.

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The Dragonfly Deer's Biography
The Wannabe Ninja

lolno.
Practice.
Practicepracticepractice.
c:
It may look like shit at first. You'll improve. Draw the strangest things you can think of, the farthest stuff in your range. It'll get better. And instead of looking for sites that teach you how to draw, find ones that provide inspiration - photos of people, places, whatever. It'll help. c:
-goes back to class-
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Bios