Census Bureau
Contains surnames in English and Spanish on the 1990 Census, age search services and access to information about individuals in Fact Finder For The Nation.

Classmates.com
Excellent site for tracking down long lost friends that you went to school with or relatives who may have registered with the site. Free registration required to use this service.

Family Tree Maker
Links to over 70,000 websites organized by categories. Message boards for queries.

Social Security Death Index
"The Death Master File (DMF) ... currently contains over 89 million records and is updated weekly. The file is created from internal SSA records of deceased persons possessing social security numbers and whose deaths were reported to the SSA."

Ultimate People Finder
Trying to locate a long lost friend or relative. Try Knowx.com and browse the public records listings. For a nominal fee you can locate a full report on the individual. Locating the city and state that a person resides in is free.

US Citizenship and Immigration Services
Contains immigration forms, statistics, studies and reports.