Recommended Books for AIME/USAMO Preparation? What books would you guys recommend to learn number theory, geometry, combinatorics, and algebra at a level appropriate for the AIME and/or USAMO? With the month of February approaching, the month the AMC (American Mathematics Competition) series takes place in, I'm realizing how much more I have left to learn.
Thanks

I find Larson "Problem Solving Through Problems" a great book. It's problem after problem organized by approaches and topics. Many of the solutions are particularly clever. Yet he breaks the thought process into steps so you can really gain an insight as to how to solve problems that look pretty challenging at first glance.
http://www.amazon.com/Problem-Solving-Through-Problems-Problem-Mathematics/dp/0387961712
