Hi:

First off, I want to say that I am sorry to hear of your loss of this guitar. It hurts to lose things but especially when they are stolen. Don't know if anyone mentioned this or not (I didn't have time this morning to read all the responses) but by any chance is there any kind of security cameras in this establishment? Sometimes a business will have even just one (when they can't afford an elaborate security camera system). Often times the camera will be pointed towards the door.

Also, I would return to the swap meet the following Wednesday's in the event that the thief might wait a week to try and dispose of it.
He/she might think the owner of the guitar would try immediately to find it (be it swap meets or pawn shops) so might hold off on trying to sell it somewhere. Just a thought...

I hope you find it. Don't give up. Have you also looked in the paper to see if anyone has placed an ad to sell it? I think someone posted a message for you to place and ad "looking for a guitar to buy". Also try Craigslist and EBAY to see if this person might have an online to try and sell it.