The folllowing books are great introductory books for learning the basic figure. Now granted, it's comic book illustration but it's great at proportioning out the figure. You can always pick up more advanced books on shading and fine details later.
The following books are:
How to Draw Comics the Marvel Way
By John Buscema & Stan Lee
By Joe Kubert
They cover everything from body proportions to musculature, hair styles to poses.
The Marvel book is great if you like drawing comics, heck, even if you're a regular comic drawing veteran it's always a great refresher course.
This brings me to my point. Whenever I tutor anyone, especially in art, it's like a refresher course for myself too! It causes me to go over the basics of technique. Kind of like an athlete that continues to drill the basics of movement and coordination. You remember why you draw the way you do, what you've forgotten and what you've remembered.
It never hurts to relearn through someone else.