Microsoft won’t accept my new credit card number for buying Microsoft Points for Xbox Live, since the card has an overseas military APO address. For anyone else in this predicament, a nice work around is to buy the points on Amazon.com and you can get an online code right away that you can enter into Xbox Live to redeem your points. It looks like they have 2 different options:
As of this writing, the prices are just about the same as if you’d buy them from Microsoft. Another nice thing about them is that you can buy 1600 points, not just multiples of 500 points. Games on Xbox Live Arcade are usually 800 or 1600 points, so you won’t have any odd amounts of points left over.
Hope this helps someone out.