np, i liked the cd from barrons it gives good practice. Remember that mathematics is all about practice. The problems will always be similar and there is a process to figuring things out in calculus.
I think its best for you to borrow books from the library or go to barnes and nobles and look through some and do problems maybe. Any practice will help you, not sure if i mentioned earlier but, DO go to collegeboard.com ap central. They have past free responses that you can do, and maybe they have answers, im not sure. Either way you can look them up or ask your AP teacher for help.