The founders of Spokeo created it several years ago to help people stay in touch with friends and colleagues by monitoring their social networks. I liked the idea and became an advisor to the company. Fast forward a few years, and the company is getting real traction from headhunters and human resource departments.

This is how it works: You enter the email address of a person. (Think about it: searching by email address is much more precise than by a person’s name. How many “Robert Lees” do you think there are in the world?) Spokeo then searches the public records of fifty social sites such as LinkedIn, Facebook, MySpace, Twitter, Flickr, Amazon Gifts, and the blogosphere. Then Spokeo produces a report of matches that it’s found.

For example, look at the results of a search for “kawasaki@garage.com” here. It shows you a great deal of information about my social networks, blogging, employment, and pictures including Flickr (170 photos), MySpace, LinkedIn, my blog, and a total of nine social networks. Clearly, I’m not a nutcase.

In particular, take a look at the social-network portion of the report. If you’re not a member, the report tells you how many social network Spokeo found the email address on, but not which ones. To see that information, you have to pay $2.95/month for one year or $4.95/month for three months.

If you do pay, you’d see much more detail (above). In this screenshot, Spokeo has identified the social networks that I belong to. If you click on the matches, you go directly to my public pages on those sites.

Now when my sons receive responses to their Craigslist ads, the first thing we do is enter the person’s email address in Spokeo to learn about the person. What happens if Spokeo cannot find any matches for an email address? That may be the scariest case—the person may really be hiding something—or simply has several email addresses or no life.

The Open Forum doesn’t typically provide advice for Craigslist sellers, but zoom out for a second. As a small business owner, you can use Spokeo to check out:

1. Buyer and sellers on Craigslist and eBay

2. Job applicants and bosses

3. Investors and entrepreneurs

4. Customers and vendors

5. Consultants and agency employees

6. Who your kids are dating

7. Who you’re dating

Spokeo searches don’t have to be an “investigation.” You can use it to simply break the ice. For example, if you’re meeting with a venture capitalist and you see that he’s in photos playing hockey, you might mention that you played hockey in college. In most business situations, it cannot hurt to do a little background research on a person before you meet.

Honestly, you could do everything Spokeo does by yourself because it’s not using any information that’s not public, but it would take you several hours. Give Spokeo a test-drive by clicking here and enter an email address—remember that you won’t see the full detail of a paid customer. There’s no doubt in my mind that finding out that you’re dealing with a nutcase is worth one Starbucks decaf, non-fat latte a month.