The best source for info on pooning in China is the World Sex Guide. Join it.
www.worldsexguide.info
I can only speak for Beijing, but the selection is very good. Two of the best places are the Hard Rock Cafe and Maggie's Bar. The HRC has at least 50 working girls there every night from about 9 PM till midnight or so. The action then switches to Maggie's. All the taxi drivers outside the HRC know where Maggie's is.
The girls are mostly Chinese (not at Maggie's, though*), Mongolian, and Russian (sometmies Ukrainian, Kazakh or Uzbek). They'll ask for 1000 RMB (about C$140) for an hour or so, but they'll bargain down quickly to 700 RMB. Nearly all the girls provide GFE level service. I saw 6 ladies in 5 nights in Beijing in 2003, and all took showers in my hotel room before the action started.
*If you're approached by a Chinese girl at Maggie's, she's hustling for drinks, not sex.