Creating Motion Graphics with After Effects: Essential and Advanced Techniques, 4th Edition by Chris and Trish Meyer
an absolute must read!
CreativeCow and the other tutorial sites it supports i.e. VideoCopilot.net, and typically any instructional site listed in posts here are good and worth a look.
CreativeCow and some of the other forums style sites will be an immense help with the incredible access the Cow gives you to extraordinarily talented people.
Lynda.com is one of my favorite resources for lots of great software tuts on a large variety of areas from After Effects to MS Word and more! But… its not free. The “basics” are free but to get into the more advanced its a pay site. And the “basics” are good!! I think its totally worth it, the lessons are timed well, easy to follow, and broken down in small chunks so you’re not overloaded.
Brian Lynn