Games Workshop apparently scrounged up some more copies of Space Hulk and are shipping them to the US. They could show up just about any time.
From the announcement:
Many of you have contacted us to say how frustrated you were that our US and Canadian webstores sold out so quickly. We listened, and we have good news!
We’ve managed to get our hands on a small number of copies, and we’ve decided to ship them to our warehouse in Memphis and make them available again for those of you who missed out.
These copies are currently on their way, and we expect them back in stock in early December. We don’t know for certain when they’ll get there, so keep watching, but you’ll need to act fast. Once these ones are gone, that’s it. The warehouse really will be bare!