For those of you who've read my book, Finding Your Roots Online, you'll know that one of my favorite ancestor-finding tools is a run-of-the-mill search engine. Using search engine "math"—1Boolean operators such as or, + ( which means and) and - (means not)—genealogists can construct complex searches that eliminate millions of irrelevant sites. And, with Google surpassing the four billion-pages mark in their Web index, we genealogists can use all the help we can get!

For example, if you're hunting for a North Carolina ancestor named Frederick Ballard, and your searches keep turning up Virginia Ballards, you can use the - (minus sign) to omit Virginia from your search results: frederick ballard -Virginia. Or use the plus sign (+) to ensure the engine picks up pages that contain Frederick Ballard AND North Carolina.

One genealogist who has used search engine math to help fellow researchers is Doug Barry, Webmaster of Free Genealogy Search Help for Google. Using the built-in form on his site, you can enter the name of an ancestor and (optionally) the name of his spouse and parents, as well as place of birth and death. Once you click the Submit button, the search helper goes to work constructing the phrases that it thinks are the best searches for you to enter in the Google search engine.

Those phrases will you help pinpoint your ancestor on the millions of Web pages Google indexes. You'll also receive tips and tricks that will likely improve your search results. The different searches give you a variety of ways to use Google for finding ancestry information on the Internet.

Although the Free Genealogy Search Help site is specifically for Google, you can use Boolean operators at virtually any search engine when ancestor hunting. Other popular engines:

• AlltheWeb
alltheweb.com

• Hotbot
hotbot.com

• MSNSearch
search.msn.com

• Yahoo!
yahoo.com