You should look for a guitar with a solid top and solid sides. The top can often times be identified as solid by simply looking at the wood grains at the sound-hole and see if they match along the rim of the hole. If you instead see layers of wood at the sound-hole, you have what is called a laminated top guitar. These guitars have poor tone as compared with most solid tops. A close inspection of these features will give you a good overall appraisal of the workmanship of an instrument.
Some Final Thoughts Learn to haggle.
Without exception, I have always received a discount from what was shown on the price tag. Don't be shy to ask for a better price. Unless there is already a sale taking place, you'll see the salesperson go get a calculator. Don't be in a rush. Take your time in choosing an instrument.