Just report it stolen... someone will ring sooner or later.
or you could try this guy
Gold Coast Private Investigationshttp://www.goldcoastpi.com.au/
I hear he is a little pricey but he pays a very generous finders fee to anyone who sends work his way.
I had him follow my girlfriend around for a while and take a bunch of photos of her. you would think
a private investigator would have clued on fairly quick, but it wasn't until week 3 that he realised I had
him following his own wife. that was a little awkward. still though, got some nice pics out it.
I said I had a plan. I never said it was a good plan.