I just started reading The 4 Agreements by Don Miguel Ruiz (I mistakenly referred to it as The 4 Promises or something earlier) and I wanted to mention it on one of Sorcer's threads because basically it seems to boil down a good deal of the Toltec teachings (same stuff Don Juan Matus passed on to Castaneda) but in much more understandable form. I'm amazed at how clearly and concisely it's explained even just in the 1st chapter - all about the Nagual and the Tonal - the False World we're all taught from birth that we need to unlearn in order to see clearly and to free ourselves from all the social agreements we take on that limit us as beings.

This book, and possibly a few others by Ruiz, are highly recommended reading material for anybody who has struggled through any Castaneda books and liked the ideas but had trouble understanding them.