I'd guess that many "career" Providers have put some effort into having a website to promote themselves and their "specialties". While some have them built and maintained by a webmaster, there are some who have taken the time to learn the craft and keep their site fresh. This would also apply to agencies.
They create video shorts, email updates and current travel calendars. Some of the former porn stars will normally have links to their clips on various other sites as well. If you're really lucky they'll even have current rates posted...
Back in DC Jessie Yum Yum used to have a quite elaborate site but has since become a Nuru specialist so focuses on that now.
My personal favorite is Zasu Knight. Especially since I "donated" a few items for her.
http://planetzasu.com/wp/?page_id=53
So Ladies and Gents... is there a favorite site you've visited?