Report it to the Police and give them as much detail as possible about your bike.
It's amazing how hard it is to recall the detail of how your bike looks once it has gone. A Cycle Passport is a good way of storing information about your cycle in case it is stolen.
(cycpp)
Listing things such as make, model, type, colour, and frame number are vital in helping the police build up an accurate pitcure of your stolen bike. Providing a recent photo of your bike is obviously an excellant way of doing all this.