College classmates tend to keep in touch more regularly than do high school or grammar school classmates. Check with your former school first, then utilize other sources if necessary.
Check with the alumni center at your former school. Most schools keep regular update forms for graduates who have kept their information current.
Scour national telephone books on CD-ROM. Many public libraries offer access to these informational CDs at no charge.
Use the Internet. A vast number of Web sites allow you to search information based on various categories. Search for "locate people" on your search engine to get you started.
Search active-duty military databases on the Internet. These updated databases provide accurate information about members of all military branches.
Use an Internet-based e-mail search. Most search engines have a section that allows you to gain access to the e-mail addresses of anyone in the world.
Talk to your librarian. Libraries often contain the pathway to a successful missing person search.
Search county assessors' offices for property tax records, which will contain owners' names and addresses.
Investigate county registrar of voters offices.
Visit marriage license bureaus to help you find female classmates by maiden name.