I've heard some pro artists (particularly Steve Rude) rave about Andrew Loomis and his "How To..." books, but the majority of his books are a bitch to find. I just found this link this morning and thought I'd post it for the aspiring artists here:
http://www.alexhays.com/loomis/There's PDF's of six of Loomis' "How to" books available there. Well worth checking out, the man was a master at figure drawing.
There's also a link on that page to another site that has the books posted as jpegs.
Enjoy.