I've never run a site or anything, but have thought quite a bit about what I would do if I did, and I think one way you might be able to find original, exclusive content is by checking out the personal, non-paysite websites of some of the babes who you would want to have on your site because many of them will have photos from shoots they did with lesser known photographers. Be it either their friends or just photographers trying to get their name out there. For instance, here's Lindsay Marie's site.
http://beverlyhillshoneys.com/ You'll see that the first set is by a photographer named Christos Sewell. There's another set by Andrew DeCarlo. Both of them are possible leads. I don't know anything about either of them, but if you check out a bunch of similar sites, you should be able to put together a solid shortlist of emerging talent.