Using their Google Maps API (or application program interface), Google has launched a map of UFO sightings at http://www.ufomaps.com/. The interactive map is dotted with "flying saucer" icons indicating where UFOs have been sighted. Clicking on the icon pulls up a short summary of the sighting, with an additional link to a more detailed report.
Thte data is from the National UFO Reporting Center.
The Google initiative is not the only site to use maps to chart UFO activity.
http://www.larryhatch.net/is a detailed effort to graph UFO activity ffrom the past 50 years or ealier, and as a sizable set of graphs, charts, histograms and other data.
http://www.ufodisclosure.com/tracks alleged UFO flight corridors and patterns near Bisbee, Arizona.
While not offering maps, another serious effort of research is at http://www.ufoinfo.com/.
Enjoy the skies!