I finished all the practice tests in the blue book, but I still want to improve my score a little bit (I'm in the 2000-2200 range right now). What's the next best thing?
Since you're scoring very high already, I would recommend the Barron's SAT prep book. There are six full-length practice tests! There's a general consensus that the practice questions in this book are a little harder than the ones on the real SAT, but if you want to be extra prepared, it's a good resource. Here's a link to reviews of some more great books for high scorers.