We can't know what you know, what you need to know, or what is available to you, so making specific recommendations may not work well.

That said, "Dummies" books and Schaum's Outlines are often great, though these might not suit your tastes.
Your best bet is probably to conference with a guidance counsellor, academic advisor, or other caring individual who is familiar with your situation.
My best wishes to you in your studies!
