Maybe the shop you bought it from has a record or perhaps it's on the receipt which I hope you kept. Even with that information, unless the service provider can track it, you don't have much of a chance of getting it back, I'm afraid.
Posting into a two year old thread won't help you get it back. Contact your service provider(s) and at least try to save yourself some money or credit. If you didn't have any software such as Cerberus installed on the phone, you have no hope of retrieving it.