Backlink checkers are little tools that find links back to you. I know you can go to google and type "site:example.com", but this will not find all of the links back to you, but just the ones that google fins relevent.

A better way to do this is to use a checker. Bellow are a few that we link.

http://www.iwebtool.com/backlink_checker

http://smartpagerank.com/pagerank-backlinks.php