By Kimberly Brown, Family Historian

If you have a rare and unusual surname, searching census records, vital records, and online databases is fairly easy. You'll be able to easily trace your family back without having to worry that you've gotten the wrong person with your ancestor's same name.

My last name, however, is Brown. Brown was the fifth most-common American surname in the 1990 federal census. So this article is dedicated to all of you who are in the same boat: those of us with extremely common surnames. How do you search your genealogy and make sure you've got the right family members with a surname like Johnson, Williams, Miller, Davis, or Brown? Here are a few ideas:

. Since you have a common surname, pay special attention to first names. When you're doing census searches, choose the least common first name in the family group and search for that individual. Once you've found him or her, you'll be able to find the rest of the family.

. Location, location, location. Locality is everything when searching for common surnames. There are a lot of Brown families in Indiana, for example. But because I know that my ancestors came from a little town called French Lick in Orange County, Indiana, I've been able to find and identify them even though they have a very common surname. If you don't know what county or town your ancestors came from, interview living relatives to get the most specific information you can.

. If you're searching within a large city, you'll find dozens of families with your same surname. To figure out which Tom Jones is your ancestor, map out each Tom Jones family. Print out a map of the city from GoogleMaps and use the address as given in the census to map each family that could potentially be yours. Then compare addresses listed on other documents-civil registration of births and deaths, military files, etc.-to narrow them down.

. Most importantly, don't jump to any conclusions. Don't assume that just because someone has the same name as your ancestor that they're the same person. With common surnames, be sure to check the names of all the family members to be sure you've got the right family. Check birthdates, too. If you found more than one family that could be yours, don't jump to hasty conclusions. Print out the information for each family, and then narrow it down later when you have more information.

Doing research on these kinds of family lines isn't the same as researching uncommon surnames. But by paying careful attention to first names and localities, by mapping out your ancestors' places of residence within large cities, and by double-checking every match, you can successfully find your ancestors-even if they have a surname like Wilson or Jones.