We use Authorize.net and they take internationa credit cardsl. The only problem is that a lot of international transactions fail the AVS (address verification) tests. We have this on our customer service page:
Unfortunately, credit card payments sometimes fail internationally. If you make sure that you have entered your billing information identically to how it appears on your credit card statement, call us or send us an email firstname.lastname@example.org giving us authorization to bypass address verification and put the charge through. Please do not click the "place your order" button over and over.
and since we've had that on there, a lot of times the international customers will just give us authorization via email. It's an extra step -- going to Authorize.net's webpage and entering the CC info there, but not too bad. I think it might also cost us a dime or something for the extra transaction.
Also, if I have a funny feeling about the CC, I will hold the order until the charge has settled.