Good two-part article at Online Journalism Review called Researching People on the Internet. Covers the basics pretty well. This is something that we'd do years ago. Someone would say "whatever happned to..." and we'd run the name through Google/Classmates/Yahoo/Switchboard/our College's alumni directory and the like to see how quickly we could find an address or, even better, a current photo. Some people were only a click or two away while others still have no known online presence.
