haha my norwegian roommates did this to me 2 years ago.
The guy kept coming after me. I told him I moved out before everyone else and he had seen the place after i left. And if he took me to court I have pictures showing the status of everything.
But yeah, as soon as I told him they moved back to norway and I only had an email address he gave up. I think we were renting from an illegal immigrant though cause he had us sign a piece of paper and didn't run any sort of background check or anything like that. Kinda funny.
Sucks for you though, I'm sorry.
Seriously though, check facebook. I get messages from indonesians all the time wanting to have my love child.
Other option is to contact a private investigator. for probably $200 or so they could get you a name, phone number with in a day.