Don't know what your budget is for books, but in a perfect world, I would recommend Gillenwater's "Adult and Pediatric Urology" along with a surgical atlas type book. I have a copy of Glenn's "Urologic Surgery" and a copy of "Stewart's Operative Urology."
Probably would not go for the pediatric book unless you think you might do a fellowship in pediatrics.
Down the road, a must for oral board study is "Complications of Urologic Surgery" by Smith and Ehirlich.