Links are continually added and updated. John Fuller and Chris Gaunt's page of Genealogical Resources on the Internet includes a complete reference to genealogy mailing lists and newsgroups. The Native American Genealogy Web Site is a great reference list from the America Online Genealogy Forum's Native American Special Interest Group. Sign up for the GEN-OBIT mailing list for a daily index. York County, South Carolina Census Index Search 1790-1850 from RootsWeb is a great example of the many ways computers and modems are good for genealogy.
Some searches are free, and full access is by subscription.
Marilyn Hoye's site is an excellent example of how to make local data available online. Her data on specific Texas and Connecticut locations is the real thing. The Olive Tree Genealogy Homepage includes lots of early Dutch New York data, muster rolls from the American Revolution and the War of 1812, ships passenger lists, Loyalists, and much more. The National Park Service's Civil War Soldiers and Sailors project is a database containing basic facts about servicemen on both sides of the American Civil War, including Colored Troops, battles, references, and leads to further study. For lookups in genealogy-related books, check out Books We Own or the Genealogy Helplist , both operated through the grace of volunteers.