Quark
Der Beste
save yourself the cost of calling germany and just do it over the net. make SURE you notify your bank that this transaction is going to happen, otherwise they will cancel it and treat it as fraud (as happened with me the first time). Of course, i used my debit card, maybe it is different if you use a credit card.
Besides, you'll have to call them at nighttime, as they are open on European day time. (which is 6 - 9 hours ahead of you)