What the Web knows about you

I concluded by searching individual social networking sites. I didn't get much here, but private investigator Steve Rambam, who runs the Pallorium investigative agency, says the amount of self-contributed data available on many individuals is enormous.

"If you have a MySpace page, and Friendster, LinkedIn, Plaxo, Yahoo 360 and Monster.com, and you use Twitter and Flickr, in 90 seconds I'll have your photo, your likes and dislikes, where you live, what you do and so on -- all contributed by you," says Rambam. That search, he says, provides as much information as he used to gather during a 12-month investigation in pre-Web days.

If that sounds scary, the technology also has its limits. "You have the best defense against a casual investigation: a common name," says Rambam. To find people like me on social networking sites requires logging onto each one individually and using advanced search features to try to narrow down the field.

"Even then there are dozens of records that would have to be manually examined," Rambam says. But that just slows him down. "It would probably take a full day to compile a decent dossier on you," he says, while a unique name takes just a few minutes.

Source: Paid searches

Information discovered: Address history to 1985; real estate purchase dates, assessed values and mortgagors; 2004 property tax bill; nonprofit affiliations; Flickr account details; published stories; parents' names, address, phone number and first five digits of Social Security numbers; current and past neighbors' names, addresses, phone numbers, dates of birth and first six digits of Social Security numbers

At this point, I decided to invest a little money to see what premium searches would buy me.

Since no one had come up with my cell phone number, I decided to start small, with a US Search reverse phone lookup -- which means you provide the number and the company traces its owner. US Search indicated that the information was available on my number -- for a fee of US$14.95.

I pulled out my credit card and purchased the report. US Search could not find any data initially. The next day it sent an e-mail that attributed the phone to "Josh (last name unavailable)." Address information was limited to a town name, which was incorrect. US Search refunded my money.

I tried other sites, also without success. One possible reason why: I never provide my cell phone number online or use it for business transactions.

Things did not go so well with USATrace.com , which claimed to offer an "SSN Search" background report on any Social Security number for US$37.99. I had picked the company at random from a long list of businesses that came up after I ran a Google search on "Social Security number trace."

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