Yep, Xenoblade will only be sold at GameStop or through Nintendo's own website. It's a bit strange and very frustrating. (I much prefer Amazon)
Anyhow, this might tempt me to buy Xenoblade a second time after buying the European version last summer. I wish we had more details about this artbook, though.
It will most likely be a cheap, flimsy bonus, but whatever. It's time to put my $25 gift card to use.