Personally, I would change all my passwords BUT the AIM one. It may be your only chance of contacting the thief. IM him/her and tell them the laptop is theirs to keep, but you desperately need your photos and documents. Tell them you will pay $500 cash for a DVD with the files. If they're stupid enough to sign on with your IM account, they may fall for it. If they do agree, set a time and place to meet, then call the cops. You will most likely need to bring $500 actual cash because the cops probably won't go for the nab until the deal is done.