That will tell you where they have appeared.  Since you are a newbie to the hobby, follow the cardinal rule for newbies, namely see only well reviewed providers with reviews by established reviewers.  However, you should also check the other review sites to see if she has reviews elsewhere.

Even though I have seen many providers, if she has no reviews anywhere that I can find, I will not see her.  The only exception to that would be if I happened to know someone that had seen her and gave me the all clear.  Remember, some providers do not want reviews for privacy reasons.

Good luck.
Swim

I`m interested in a provider who hasn`t been reviewed here and I haven`t contacted her because I`m worried her pictures might be fake. What`s the etiquette in a fake photos situation? Have you been in this situation, what did you do and how did she react?

As this is on the Newbie board, I must assume that you are new.  Newbies should not see unreviewed providers...  in fact should stay to well reviewed providers.  Even vetran hobbiests see mainly well reviewed providers most of the time.
Once you have learned the ropes, there will be plenty of time to circle back & check this hottie out.  
At least you checked to see if she had reviews...  that's the first step.
skb

All right, I'm relatively new to this, too, and we're not supposed to flame on this board so I'll step up to bat.  Please read this thread back for a few pages and also read the self-help "newbie manual."  This question and virtually any other you have will be answered there.  It's really better to do your homework first before asking the very generous and patient vets on this board to write the same answers they've been writing for years.
In the spirit of giving, here's my answer to your question, but PLEASE also do your homework before asking another "Newbie 101" question.  Thanks and enjoy!
If you arrive at an incall and find the provider looks nothing like her pix you have no obligation to go any further.  It is perfectly acceptable to say, "Sorry, but you're not the girl in the pictures," turn on your heel and leave.
If you find, despite the B&S, that you're still attracted to her by all means forge ahead.
Finally, if you're a newbie this is one more reason to stick with well reviewed providers who also have web sites.  But if you get B&S in this situation, the above points sitll apply.

for tineye and you will see several posts on how it works and its value to uncovering a provider using pictures from who-knows-where.

It's not infallible, though, simply one more tool in the toolbox for vetting providers (and like others have also said, newbies are recommended to see only established, well-reviewed providers while you're getting your feet wet). TinEye.com also has plug-ins for the major browsers (Firefox, IE, Chrome, Safari) that'll allow you to quickly scan a photo by right-clicking on it. Very useful, and drop-dead simple.