I'm gonna take a sample GMAT soon to see how I do w/o any preparation at all. Then no matter what I get I'd like to take a prep class. My friend took a Princeton Review course and didn't care for it. She recommended Manhattan which is kind of pricey.

Are classroom based classes generally better than online for this sort of thing? Any recommendations for classroom or online? I'm in the US.

It depends on a couple of factors. You're right about the first step - to find free computer adaptive test online. Should be pretty easy to find - all the big test prep providers like Veritas and Princeton Review have them.

By taking one or more of these practice tests, you should have a good sense of your strengths and weaknesses. Look at the stats for the programs you want to target and see if your score is within the average ranges.

If you're a good independent studier and your practice scores are within a reasonable range of those from your targeted schools, online test prep courses should suffice. They're usually substantially cheaper, and are usually comprable to classroom courses in terms of deliverables. Some students find that it's more difficult when you don't have personal contact with the instructor, but many find the experience satisfying. Many of the online courses also provide assistance and feedback on your essays, which for many students can be complicated since they're graded objectively.

Classroom-based courses are much more expensive, but many students find that they lead to bigger score increases. I think it ultimately depends on your practice test scores, and whether it's worth it to you to have hands-on training.

Your other option would be to use a book or online program to self-tutor. This method can also be used in conjunction with a class to get an extra push, especially with the quantitative section.

Hi..I did a lot of research when I started my preparation (take a loot to gmatclub forum , manhattan forum, ecc)
Generally (I found lots of people that agree on this) you can take one of the 2 free official test.. if you score within 100 from your target you can prepare on your own (Manhattan, Veritas books). If you are not in the 100 points range consider to take some classes.

By the way if you consider some private lessons:
1) if you are an engineer or something similar you don't need a teacher to have math questions explained
2) if you have problems with verbal section be aware to buy lessons from private teachers (with no GMAT experience). I bought some lessons from an american institute in my town.. the teacher was good but I had a better score than him in SC and CR :-) (but it costed me 300e as well ......... )

The most important part of the preparation is motivation... try to keep it high as much as you can... Unfortunately I couldn't and now I'm in trouble. Some very basic tips from my bad experience:
1) study in the morning or at lunch.. in the evening your score goes incredible down (after a day at work...it's not so easy)
2) try to do the prep tests always on the same day at the same hour (and wait to take them... studying in much more important in the first phase)
3) keep your material far from your girlfriend/boyfriend.... when my girl (doing housework) thrown away the 2 month list with all the wrong answers (that I planned to study deeper) I understood that faith was against me :-)

Good luck!

Thanks for the suggestions!