Hey chgoshark,
The down spas have probably the best example of YMMV that I have ever seen. There is nothing neer St. George, but lots along Bloor in either direction.
To the east there are a handful of places at Yonge and Bloor (29 East and that little place just south of Bloor, I think on Hayden Street). Both are okay, mixed with Asian girls and local Canadian girls. I haven't been to either in years, got bored and never found anyone amazing that I clicked with. Some one mentioned a new place on Yonge Street (Do a Search for Yonge St).
To the west there are more places too. There is an EE place at Christie and another one just east of Dufferin. There was an Asian place at Bathurst and Bloor, but it has moved west ..Young Man.
I find all of these places fairly mixed experiences. It depends on the day and the girl ...as I said YMMV. None of them are conistently great or good. The other place mentioned by oldjones are further west or further north by quite a distance. They may be worth the trip...but they are a distance from your location.
Good luck...it's a jungle downtown and you may be better off at a strip club.
DrTroff