I know when I post reviews, it says an ad website and/or personal website are required. However, if I visit providers that either a) only have a profile on another hobbying website that TER doesn't allow linking to, or b) don't have any online presence at all, is there any way to review them? I figure it would still be useful to other hobbyists to look up their reviews based on their name, email or phone number.

The best you could do is ask them to get onto one of those free escort mall sites like City Vibe and then you'll be able to review her.

If she wants reviews, you'd think she would be open to that.

also it must state there name

I found her via another hobbying website that I'm told TER doesn't allow naming/linking to --so I'm assuming listing that as her ad page is out.

But the question would also apply to anyone found offline - via a friend's recommendation, for example.

Either a personal website, or an ad that you can link to in her review.  If she has neither, you cannot post a review of her on TER.  Simple as that.

Swim