I thought that one of the best books for the Surgery Shelf is PreTest. It will kick your ass the first time around, but if you can learn by doing questions, there is a ton of info in their answer explanations. Also Appleton & Lange's question book for Surgery was very good, and much easier than pretest, so it gives you some confidence.

I will agree with orthodreamer. Pretest is the best for the shelf. Throughout the year last year, if I used pretest I scored in the 90's if not it was in the 70's. (4:2) I found that A&L had many obvious mistakes where even thier own explanation contradicted thier answer but it does give you a little confidence. NMS was a good source to read from as you can skip through a lot and they also provide questions.

Good luck,
Richard