How do I get my money back ?

Recently a Arab Man knocked on my door he was dressed in a nice suit drives a jaguar xj and said he was from dubai, He then said if I payed him �100 upfront he could get me a trip to dubai where I would stay in the Burj Al Arab for a month, so I payed up he then told me he would be back the next day with the ticket. That was 2 days ago, He probably tied up with paper work and that but now I have decided I don't want to go please help me get my money back thanks.