Car broken into... what can be done?

My friend is visiting from Colorado. She checked out of her hotel early in the day so all of her stuff was packed up in her Jeep. We went to Pike Place Market and parked in the "official" Pike Place parking structure under the bridge. In the few hours we were there, somebody smashed in her rear window and helped themselves to exploring her stuff. Everything was hidden as best as it could be, but Jeeps don't have proper trunks so there wasn't much we could do to hide that there was stuff in the car. They went through everything, made a mess, and stole her laptop, a 17" silver Macbook Pro with Wil Wheaton's autograph on the front. It currently doesn't have a case, so to bring it with us to the market would be to carry it around out in the open. Buried in the luggage it stayed. On top of being an expensive bugger, the autograph gives it a huge sentimental value. The police could only shrug and point to the sign on the wall that says "don't leave valuables in your car." Yeah, big help.

The garage is not liable (because of the sign) and the police don't seem to want to do anything, so what can be done now, if anything? Where do things like this turn up? I feel bad because I talked up how awesome this city is forever, and when she finally visits, this happens. I want to help in any way I can, but I don't know if there's anything I can even do. She feels so violated, and on top of it she has to drive her Jeep with the busted window all the way back to Colorado.

Advice, Reddit?