When I went back to school to complete my degree, I bought and used this book religiously and I have to say that it really worked for me. Having suffered from math anxiety my entire life, thanks to some real loser teachers from first grade on, this book allowed to me confront my fears and work through them.
As a result, I managed to be a straight-A student through 6 semesters of algebra and trignometry. This book allowed me to realize that, while I'll never be a math genius, I'm actually pretty good at it and actually enjoy it. Highly recommended for others.
Just do all the exercises and learn to desensitize yourself to the negative thinking and anxiety that math brings to you & you'll see a definite improvement in your ability to problem solve and think critically about any kind of math.