Rootsweb.com - http://www.rootsweb.com/
The Internet's oldest and largest free genealogy community. Home of the Rootsweb Surname List, with over 800,000 surnames listed; about 18,000 surname, ethnic group and locality mailing lists; and the WorldConnect project containing about 23,000,000 names.
USGenWeb Project - http://www.usgenweb.com
Volunteers host pages for every state and county in the U.S. May contain transcribed census or vital records, surname lists and queries, military records, biographies and more.