Hi Henni,

If you want to study from those books, then that should be fine (the material in those books is still relevant to the current version of the GMAT). Since your friend already used those practice CAT tests (and the codes are several years old), I'm not sure if they will still be usable. Depending on your score goal, it's likely that you'll need additional practice materials besides these books though.

Since it sounds like you're just beginning your studies, then it would be a good idea to take a FULL-LENGTH practice CAT Test; you can download 2 for free from www.mba.com (and they come with some additional practice materials). If you want to do a little studying first, so that you can familiarize yourself with the basic content and question types, then that's okay - but you shouldn't wait too long to take that initial CAT. That score will give us a good sense of your natural strengths and weaknesses and will help provide a basis for comparison as you continue to study. A FULL CAT takes about 4 hours to complete, so make sure that you've set aside enough time to take it in one sitting. Once you have those scores, you should report back here and we can come up with a study plan.

I'd like to know a bit more about your timeline and goals:
1) What is your goal score?
2) When are you planning to apply to Business School?
3) What Schools are you planning to apply to?

GMAT assassins aren't born, they're made,
Rich