Not available internationally.
Oh well, I have four paper copies including the Kaja Foglio-illustrated omnibus and the Subterranean deluxe hardcover omnibus and the French translation to comfort myself with.
that Weightless Books gets it and offers another DRM-Free Day or equivalent deep discount sale since according to Charles Stross' blog, sometimes it's the stores which are a lot pickier about applying geo-restrictions than the publishers want them to be.