This post won't be super helpful to most, as (due to unusual academic / innate comfort with language) I studied for under 15 hours for the Verbal, IR, and AWA sections combined, but here are my miscellaneous tips for the test in general, with a slight tilt towards the quant section. I actually feel like I left points on the table (see #2), but won't be taking it again, as it's almost certainly not a good use of my time.
1) Unless you really, really think you need a tutor, self-study.
Manhattan Prep is ~$100 on Amazon and had way more information (and practice tests) than I needed. Just force yourself to sit down and work through a book, outlining stuff (perhaps on notecards) that you need to learn / brush up on, every few days. Saves money and teaches you discipline. Shoot for 60+ hours and focus on weak areas wherein you can make tangible improvement. I did about 75, with ~80% of it focused upon quant.
2) Schedule your GMAT (somewhat) in advance. I thought I was slick and would waltz into a Pearson center a few days after a practice exam hit 760+ (I only took the two official practices, and parts of one Manhattan), and therein carelessly repeat the feat. In fact, I had to wait over a month between 'finishing' studying and my actual test date. Though I did my best to stay sharp, I was highly annoyed that I had to, in effect, re-hash everything I'd previously mastered, and definitely left points on the table, as a few things slipped (the most important being my sense of timing) my mind.
3) Take all your practice tests on a computer, ideally with a whiteboard like the one used in testing centers, under testing conditions. I didn't learn about the whiteboard until the morning of and, though it is less annoying than it may seem, it's still not a perfect replacement for a pen and paper.
4) Read super carefully on quant questions, including after you've answered it just to make sure. Quite often, there is a wrinkle that they slip in that totally changes your pathway and answer.
5) Don't waste money on a GMAT unless you're reasonably sure you'll hit somewhere in the neighborhood of your desired score. MBA dot com has two free tests, and ~4 more to purchase for a very reasonable price, and I've found they do quite well in approximating your score. Even if price is no object, taking and bombing a GMAT prevents you from re-sitting for 31 days, which is a long time to have to maintain your levels of knowledge. The
Manhattan Prep CATs are WAY harder than the real thing, so use the MBA ones as a barometer (and the Manhattans more for practice).
Feel free to post any other questions you all may have.