Maybe it works better for Candians than for Europeans. At least this particular European...
I have a US address, use that as the credit card billing address. They do accept my credit card, BUT when trying to get an order through it doesn't work while I'm in Europe with a European IP (I can't be bothered with VPN). It has nothing to do with the credit card, cause I can't even get the freebies.
Hoping it works better for you though!
(And really, to me it's no big deal. I don't actually have a Nook YET (I will in a while), but I've done lots of checking around. If I find a good priced book at BN it's usually same price or lower at Sony's store that DOES work for me. Most of my books I actually borrow from libraries. Free and convenient!)