What are the best AP test prep books?

I took AP U.S history and i found that the paper back book you receive along with the regular textbook is the best--there are flash cards too but the book goes more in depth, but isn't as big as the regular textbook. Honestly the best way to pass is to MAKE SURE you learn things when they are being taught so you can ask questions; taking notes can also help as long as you aren't one of those people who copy down the entire book, and this is coming from someone who has passed all his AP exams--got a 5 on AP US. You shouldn't have to study like mad right before the AP test; i noticed the people who did that were the same people who would copy down every other word of the book....and got 3's or didn't pass. Good luck! And remember you ask enough questions so you understand the content before you move on to the next!