A new player in the very active online real estate listings competition is PropertyShark, which, unlike Zillow, provides the current owner at an address, and also customizes demographic maps for the geographical region of an address.

At the Zillow site you can look for real property valuations and aerial photographs by property address. It covers many more cities than does PropertyShark but the tools at this site are a unique supplement to the other property listing and mapping Web sites.

A PropertyShark search by address (after free registration) returned a profile with the current ownership, last deed transfer, demographic maps, building permits, neighbors and nearby property sales. Coverage is strongest in New York, particularly Manhattan, for which there are photographs of properties, but take a look at all the site features. Cities in New York, New Jersey, Ohio, Florida, Texas, Washington, Oregon and California are currently included.

Map your life in Los Angeles and plot crime and property sales within the circumference of a specific address.