I live in a small city. There's quite a few providers on backpage but none of them have been reviewed. I visted one, she was decent and I reviewed her, but it wouldn't get posted because they felt unsure of the provider (and maybe me, I don't have a lot of reviews). Nonetheless, nobody is reviewed in my area (not for a couple years).

Is their any reasoanble way of picking someone who hasn't been reviewed? Any strategies? It's hard to tell by looking at the pictures or ads. One claims to have reviews (she has no e-mail) but I can't find any anywhere. And her number and name changes frequently, making me skeptical.

Is there any good way of stepping into a first timer or should I just wait a couple years until someone posts a review?

Seeing an unreviewed provider is a crap shoot, anyway you look at it.

She could be a rip off, upsell, bait and switch, or just lousy service.  Either way, it's kissing hard earned money good-bye.

There are a few things you could do, none of which guarantee anything.  You can Google the phone number, and if it appears in multiple ads it means agency (which means stay away).  You can use Tineye.com to check to see if the photographs have been taken from somewhere else.

Also, if the ad says "you won't be disappointed" you probably will be.  If the ad says "it's me or it's free" don't touch it with a 10 foot pole.  

But, the smart money says don't bother with unreviewed girls at all.

Thats not a fair statement. Just like saying providers shouldnt see a guy with no references from another provider. We all have to start somewhere. I understand you have to be cautious regardless,from both ends. Alot of girls prefer not to be reviewed as well. My suggestion is to speak with them on the phone first, get a feel for how they are.

I would never encourage a newbie hobbyist to see a newbie provider with a "couple" or no reviews. There are too many things that can go wrong.
Everyone does have to start somewhere. New hobbyists should only see well reviewed providers as a general rule. That's the place for him to start.
Once he gets some experience under his belt he can develop that "feel" that you mentioned.  

Some areas just don't have a lot of traffic on here.  You may have some success on the "In search of" board, or you might need to find a more local/regional web site that covers your area better and use that to suppliment this one.

IF you have loads of money to burn by all means go for it.   Since I have to budget for theses activities I prefer reviews.  I will only see a provider at a knowned agency with one review tha  I have previously used before.