They've Got Your Number (and a Lot More) - WSJ.com

Another reason to think twice about posting anything... 

Since the dawn of the Internet, it's been possible to plug a name into a search engine to see what turns up. And for years, background-checking services have sold expensive online services for looking up personal information such as criminal records, marriage records, addresses and phone numbers.

But now, directory companies and several start-ups are offering new people-search services that are more comprehensive and useful than the classic Google search at a fraction or none of the cost of a traditional background check.

 

Source: They've Got Your Number (and a Lot More) - WSJ.com