Internet Tip: Find Home Prices
www.domania.com  claims to have over 21 million listed houses in its database, which is searchable by address (it returns most recent sale price of homes in the neighborhood) or by price (it returns addresses in a given price range in the neighborhood you're interested in.)
It only lists about half of the states in the US, but if you're looking in the half they do have on file, this is a quick and free way to check home values.
Try it out . . .