Bone Tool Tutorials

Basic Bone Tool-

http://www.youtube.com/watch?v=EcNGeIV0BsU

More Advanced Bone Tool-

Rigging a snake with Bone Tool

http://www.youtube.com/watch?v=IFs2lTu-etI

check out rigging on BlenderCookie.com
http://cgcookie.com/blender/2011/12/12/blender-introduction-to-character-rigging/