Here are some of my own custom written tutorials and links to great tutorial sites on the net.
Speeding up the viewport (Ver.4+)
Reshaping Bones (Ver.4+)
More Morpher Tricks ( Ver.4+)
Feel free to post your favorite tutorials using the comments.
The Hobbit Guy: Dave K’s Poly Head Modeling Tutorial
3D Tutorials & CG Tutorials
Anatomy and Physiology Home Page