I am really sorry to hear you got caught up in this to, I found out last week and its gutting. You will need to contact your bank and tell them what has happened. They will then tell you that until the event has passed they are still "technically" in the post! Once the event has passed then you can fill in the relevent paperwork and hopefully, if you still have them, the emails that you had giving you payment confirmation.
I have also made a note of the website address and also this website so that my bank can see all the evidence that we have been scammed. Once you have contacted your bank then forwarded all the relevent evidence they will then investigate it and then a refund will be given. I am with Natwest and I paid for one ticket on my Debit card and they have assured me that getting a refund on that ticket shouldnt be a problem, however, I also paid for another ticket on a credit card and they have said that due to it being over 6 months they will investigate but wont refund. Apparantly its down to banks descretion. Please can I strongly recommend that you also contact Action Fraud regarding this matter, its all very well getting money back but the disapointment of being let down is just as bad, they need to be stopped.