How to report a stolen iPad when I have the serial numberl

Stolen: My sticky finger brother-in-law stole a 32 GB iPad from the lost and found in a hotel in December-ish 2013 and I would like to at least report it in some way to ease my conscience. It drives me wild to do nothing while he gets a "free" iPad, yet someone paid good money was robbed. Sorry, but I am have an exclusively Apple household, paid for legitimately, and would never want another person to stand by doing nothing as I have.

Does any one have any suggestions, especially those not involving the police directly (I do not have the iPad in my possession, but have several clear as day photos of the serial number).