Deborah, in most locations, most realtors would be more than happy to provide you with a free comparative market analysis. This will show you what has sold in the last six months in the neighborhood you are interesed in. This is a service that will cost you nothing--actually, as a buyer, you pay nothing for the services of a realtor--the seller pays the commission fee. Ask a few people who they would recommend, but remember a few rules in comparative market analysis:
1. It is NOT an appraisal.
2. It must be done on property in the same neighborhood
3. The properties used should mirror the qualities of the house you are looking at in age, location, setting, square footage, and improvements. In our area, a pool might add 10,000-15,000 to the value of a home for value, but may very well not affect the saleability of a property--some people don't want pools.
Do not look at the tax records to see what the value is, since this information can be extremely misleading--you can't see all the facts on a tax record, such as improvements unless they had to apply for a building permit to do the work, which frequently is not the case.
Good luck, and, to protect yourself, use a professional realtor!