to get a lot of pornstar content you're going to have to deal with Matrix Joe. OR what about your contacts at Legend - they probably have stills of most pornstar chicks.
http://www.xxxcontentdirect.com also has American pornstar content.
http://www.cloud9content.com has some,
http://www.sexiercontent.com has some,
http://www.freshphotos.com has some but for some reason they never got around to identifying the pornstars in their sets.