try taobao....

http://list.taobao.com/market/hobby.htm?spm=1.1000386.185136.22.3e1b68&cat=33&style=grid&viewIndex=1&yp4p_page=0&commend=all&user_type=0

http://www.amazon.cn/图书/b/ref=sa_menu_bo0?ie=UTF8&node=658390051

This is a good website for buying books. The prices are cheaper and they deliver goods very fast, mostly in or two days.

I hope it can help you.

Haven't heard of any wholesale market for books, books are heavily controlled by the government, so it is difficult to find any decent book stores here.  I've seen a couple smaller stores sell fake copies of books in poor translations, but never the real imported books. The only time I ever encountered a wholesale book selling was during the Southland Book Festival about a month ago at the Pazhou Exhibition center. I was up to my eyeballs in a sea of books for miles, I had never seen anything like it. Have some patience, they do it at least once or twice a year in GZ.

Buy on Taobao or Amazon, or make a cheap trip on the weekend to Hong Kong, where you can get any book in the world.