Prices being asked by resellers for Volume 1 are
insane but Volume 2 is currently still US$49.95 from the publishers:
Collector's Guide Publishing home of Apogee Books (cgpublishing.com). That's all Volume 1 cost back when it first came out. Apogee are now asking US$245 for Volume 1, and I doubt you'll find it cheaper, but maybe they'll do a reprint one day?
Volume 2 isn't
quite as good as the first (more interesting background/development info than useful detail) and both are frustrating for all the stuff they
don't show - and printing so many images so
small when the pages are
so big.
Must have been agony cutting up that space station.