I didn't read the thread to see whether you have a claim against them or not, but whoever does is probably better off starting with a civil route instead of criminal.  You can hire a lawyer and have him move on it ASAP instead of waiting for authorities to figure out what the hell bitcoin is and whether a crime has been committed.  The barriers are much lower for things like subpoenas when doing a civil trial.  Once you get to the discovery phase you'll be able to get all kinds of information about Coinbet's operations which then can be handed to the authorities on a platter.  It's good to get the authorities involved very early on because they will help to gather evidence, but hiring a lawyer for a civil path would be my first move.