**UPDATE - GREAT NEWS!**
My family was able to find the original packaging that my Macbook Pro came in and I now have the MAC ID#s (Ethernet and Airport IDs). I can see my computer in my Kismac data, but the odd thing is that it shows up in 5 networks! That doesn't make any sense to me, any ideas guys? Of course, I sent this updated info to my detective working the case as well as all my Kismac data. We are so close to getting it back I can smell it! The Detective has already expressed that he is ready and willing to do what it takes to get a search warrant once we pinpoint the residence by identifying the network.
To reiterate, literally I can see my Apple computer with my unique Airport MAC ID# connected to 5 different networks all in that area. How is that possible, could Kismac be glitching? All of the networks are encrypted except one which is open.
I was hoping after discovering my MAC ID # that I would pinpoint the network immediately but now this...what's going on? Thanks is advance guys!
I'm not sure how this could be happening. As far as I know it'll connect to one network only. I don't know if it's a Kismac glitch or something but honestly without looking at the kismac file I'd have no idea. What channel is it using?
I think you should give Apple another try at this point. Call them up and give them the serial, the mac address, your iCloud credentials, and ask them for the IP it's connecting from. If you've got a case number, that might help things along, and specify that this is not the thief's data. You're asking for YOUR data, specifically the IP address that YOUR iCloud account is connecting from. Ask if there's a log of connections - I'd be surprised if there isn't. Polite but firm is the way to go, and ask of there are names or numbers you or the police can call if you get stonewalled.
By the way, do you have an iTunes account? That might be another way to go, especially if you have your iTunes password saved in iTunes. Check for purchases.
-the following is of questionable legality. IANAL and you do this at your own risk-
You can sniff with kismac again and do a "capture everything" on the channel that you see the macbook. if the network is unencrypted you'll get every connection the person makes and a lot of traffic in clear text (unencrypted webpages, IM conversations, etc.). You can parse this data in wireshark and you can nail it down to the person using the computer with this data. This might not be legal since you don't have permission to be on the network. If you have to hack the password for the network (there are tools out there) then it's definitely illegal. The information is pretty much unusable anyway since you can't explain how you got it without exposing yourself to legal risk.
Also, look at the link I gave you earlier with the names of people living on that street. Maybe one of them goes to the college you go to and is the perp. I don't know if student attendance is public record or not but you could always try it. Call your school and ask "Does X currently attend the school? Does Y currently attend the school?" If they say no then oh well. If they say yes then it's one more data point to hand to the police. They could have bought your laptop at a yard sale for all you know, so there's no guarantee that they're the thief. But it's something.
I understand the officer's logic: If the network the laptop is on is encrypted, that means that the person who runs it either gave the password to the perp, was hacked by the perp, or is the perp. Two out of the three options mean that they know who has the laptop and a search is warranted. The third would be explainable as an honest mistake. If it's not encrypted, there's no relationship implied and it could be a neighbor with the stolen laptop just taking advantage of free internet. The flipside of that is you can connect to the unprotected network yourself and go to whatismyip.com to get the IP, and get kismac to keep every packet it sees which you can scan through for clues to the current user's identity.
I think calling Apple is your best bet. Second best would be a close-up wifi scan to find where the laptop is operating, but it's probably dangerous to walk around in that neighborhood with an open laptop. It will likely either get you mugged or give away that you're still looking.