You can't buy BTC direct from NT site (however you can deposit that way--go figure), but there are several exchanges which purport to allow you to buy BTC with NT.
Any veterans here know of a reputable exchange/company to accomplish this? You have actually bought BTC with NT?
Maybe SBR could vet some savvy euro dudes on here who could provide this service. Since the NT card was taken from most of the world except Euro, I am sure there are plenty of people who would like to purchase BTC with NT cash.