heh, I'm in france, I have a french credit card and a french bank account and I successfully purchased a copy on the japanese dlsite
It gave me a hard time figuring how to pay but it was worth the effort
first, you add the item in the cart then go to the cart section (it's the button with the shopping cart on it, if you don't see it, you're blind)
then you clic on the
button to access the payment page (for occasional purchase)
then you fill the form like this
1) full name
2) credit card number
3) expiration date
4) phone number (supposedly never to be used)
5) email (seems like the site doesn't support hotmail)
6) confirm email
7) the two checkboxes are for the newsletters you want to receive
8) the 3 radio buttons are used to indicate what type of newsletter you want to receive (html, text or none well, I selected the last, since I don't want to receive those ^^)
9) clic on the first button to validate and it should work