but I wouldn't get one at a pawn shop. Especially not knowing what you are looking for specifically and probably not able to tell a clunker from one in great condition. Just go to a place such as www.musiciansfriend.com as they have many in your price range and you can send it back if it's got some problem or whatever. You generally can't take stuff back at a pawn shop.
I've purchased 2 guitars from Musician's Friend and the transaction went great. One of them I even sent back for a very minor flaw in the guitar and they sent me another one right out that was perfect.
What brands are good? Everyone's got different opinions on this but for me I would probaby go for a Washburn or Fender or Epiphone brand. I've owned guitars in all of those brands that have sounded great. Musician's Friend also has reviews so you can see what other people say about the guitars.
This looks like a good one right here:
http://guitars.musiciansfriend.com/product/Washburn-D9-Dreadnought-Acoustic-Guitar?sku=502031Good luck!