I had my MBP taken with http://preyproject.com/ installed. Now I live outside the US , (in Ireland) and while the police where helpful & curious about how the tech worked, they just did not do anything, even though I got a photo of the guy, his first name and geo location of his apartment block in the first week.
So 3 months later, and although I'm still watching the guy watching porn on my laptop, I have built up a substantial profile of him, through persistent (obsessive according to my girlfriend) tracking.
So just this week I passed on the following details to the cops - fullname - email - phone number - postal address - bank account no - online betting account no - lots of photos of him and his flatmates/friends.
They were kinda shocked I was still on the case, but said they will dispatch someone to go pick up the laptop this week.
So my advice; if you stick with it, and hand them the case on a plate it might work out.