Advice? Use Google. This has been beaten to death.
I used to be a little annoyed at members who'd reply like that, but after some years on the internet, I'd be a hypocrite to be pissed at them for that!
At any rate, I'll try help, but I'll keep this brief.
Your main study book will be the official SAT guide. The Blue Book. I didn't find the explanations worth my time, and many will agree that you're buying the book for official exams. Depending on how bad you are at the test, you may want to save some of those exams and do one from another book.
The math and writing sections are the ones which you can really "drill" for. Critical Reading is a whole other beast, and other than practicing from the Blue Book, reading with comprehension, and reading faster while maintaining comprehension, and answering correctly (duh) with confidence, there is not much I can talk about.
For writing, you want to buy Erica Meltzer's book. It is the perfect resource, afaik. She also has a book of exams she wrote herself. Her book will teach you grammar, but only from the perspective of the test. Everything is geared towards the test and nothing else. Of course, what you learn will also help you with writing in general, but if that's your goal, you'd be better served with a book suited for that purpose. I hear Elements of Style is a good one, but I haven't read it.
But yeah, Erica Meltzer. Her book. Assuming you possesses a moderate amount of intelligence, this is all you need to get 750+. I'm not a native English speaker, and after correcting the issues I had (admittedly, they were not numerous), I would drop only 1 or 2 points out of 49. If I recall correctly, each answer comes with an explanation, and she also references where she talked about it more lengthily (i.e, the relevant chapter) in her book. She also has that for the questions in the Blue Book.
On her website, she also tackles the essay portion. I listened to her (some other people tout that method) and I got 10/12 (or something...) in the essay. The gist of is this: coherent arguments, relevance to the question, and for the love of god, FILL all pages.
For math, PWNtheSAT is good. Heard people say good things about Dr Chung's book, as well as Barron's. That said, the Blue Book coupled with Khan Academy (there's also 2 other guys who have videos on their website and lots of SAT math resources, can't remember who) should serve you well. Practice. A lot. When the material is this rudimentary, it's easy to get bored, but time is of essence in this test. And sometimes, you get very tricky questions or you're just tired/sleepy or panicking.
Any other questions, use Google. Or somebody else will be kind enough to answer. I think I've covered this well enough.
