Text request--Abhidhamma I am looking for a legal, online version of the Abhidhamma in English. Can anyone point me towards some good online sources, especially for the major books of the Abhidhamma?
The "Comprehensive Manual of Abhidhamma" is an excellent translation of the Abhidhammattha Sangaha with extensive explanation / charts by Bhikkhu Bodhi. It can be legally downloaded from:

CMA

There are scanned copies of some of the Abhidhamma Pitaka available at:

Dhammasangani Pali English

Vibhanga Pali English

The Pali versions appear to be legal, the legality of the English versions is questionable. 

My strong advice to you is to start with the CMA. Only once you have truly mastered this text should you even consider looking at the original Abhidhamma Pitaka texts.