Whats a good website for tracking numbers?

I lost my 32gig 4th gen ipod touch and am getting calls from a guy who claims to have it and is calling me threatening to kick my ***. I've tried to track him using a few sites but they only give me wrong infe.g.( they would say that the number is from Kent, WA, and then after i pay 5$ they'd say he lives somewhere else, with no other information.