Call your bank ASAP. I had a bunch of $$ disappear from my checking account (before I ever started buying from Hobby King); once I assured them that I absolutely positively hadn't bought a Really Genuine Fake Rolex Watch from Bulgaria, they were able to get the charges reversed, except for $5 or so, which I was willing to part with given the circumstances.
Let Hobby King know, too -- if they care to do business in the US, they should care to plug whatever leak they have. I've bought from them without problem, and I others here have, too.
If you do contact Hobby King please let us know what they said -- if they help you fix the problem that's points to them; if they blow you off, the world should know.