Have you tried using Google Alerts?
Google Alerts will search for your long lost cousins on the Internet while you sleep.
To create a Google Alert, enter a topic you wish to monitor in the search terms box, then enter your e-mail address.
Every time there is a new occurrence of that search term on an Internet page, you will receive an e-mail about it.
If you enter a surname you are researching, Google Alerts will tell you whenever a new family tree or Facebook account containing that surname appears.
This works especially well when the name you are researching is uncommon.