jonnythan said:
Easy.
Call the number on the back of your credit card and tell them you were scammed.
They should give you the money back right away, and then they will reclaim it from the scammer.
Credit card companies are exceptionally good about nailing people who defraud their cardholders.
What Jon said! I used to work for a credit card company setting up these types of disputes. They can take time to be finalized, but the company should give you what they call a conditional credit and then when they get the money back from the scammer, they'll make the credit permanent.
Also, ask them about having your credit card number changed. It's the only way to prevent the scammer from continuing to charge your card.