When you register, GRE sends you a prep cd...though it didn't arrive till after I took the GRE so I have no idea if it helps. I read a tiny bit of the Kaplan book for verbal, and took one or two old Kaplan practice tests. Truth is, the quantitative is very very similar to the DAT; the writing is like your freshman college writing class; and the verbal you really either know the words and analogies and are familiar with the reading passage content or you aren't. You can try to study for the verbal, but will probabl end up saying to heck with it and just taking the exam. At least I did.
I probably spent about 15-20 hours over 2 weeks. And I would have done the same with 5 hours. It may be wise to find out how seriously the ortho programs you are applying to consider the exam (some want you to do well; many just list it as a requirement because the university Graduate School office--who grants the MS degree--requires it for admission). Good luck. 🙂