Mooh had a lot of good advice. I'll add that it's great to be able to take a friend that you trust to help you. That way you can hear the guitar being played. I'm leary about some of the sales help that can be found in a lot of stores. They're not all bad of course but many of them { in my experence } are far more knowledgeable about electrics than acoustics. And a lot of stores stock a large supply of dreadnaughts and have very few OO , OOO and OM sized guitars. Try as many sizes as possible until you find one that fits you. You'll know it when you hold in in your arms. And there are some very nice instruments that can be found for under $500.00. Know your budget. You don't have to spend $3000.00. But wouldn't it be nice.......