It should. You don't need to create a new account. Just change your online account information that's used with the 1-Click buying in your current account and that should get you to a UK print site so you can ship to a UK address.
However, I may have been wrong in my first response. In the iPhoto 08 Order and Printing Options the following is stated about European orders:
+Customers with a billing address in Europe can have their orders shipped to any European country where iPhoto Internet services are available. To see a list of countries where Internet services are available, see Related Topics below.+
I should imagine that hasn't changed with newer version of iPhoto. The original document is
Which regions and countries print products can be shipped to.
Don't know if you have time to contact Apple at
http://www.apple.com/support/photoservices/contact_us/ to see about your German credit card.
