Lensesnmore - I got duped, now what to do?

[Ric360]

On Friday, I ordered a new camera from Lensesnmore. This afternoon (Sunday), I was called to verify my address before shipping. Just like everyone else who has been scammed by this company (and others this guy owns), I got lied to, mislead, and then charged more than double what I had originally agreed to pay. As soon as I received the verifying email from them, I realized that it was ridiculous and called them to cancel my order. Of course, they were closed. I then called Discover to see if I could possibly block the charge from going through. Apparently the charge had immediately been processed, and I was told to call the merchant first thing in the morning to see if I could cancel the order. I was told that if I still had a problem, then I could call them back and they would see what they could do.
In the new invoice sent to me with all the "up" sold charges, it actually states that there is a 7% cancel order fee. Since I never even saw this before the charge, can they really get away with that?
Should I call Discover card again, and see if I they can do something about this? Give me some pointers as to what I can do now. Thanks!