Hello Matthew,
I contacted the publisher, and was informed that due to a series of
misadventures (involving publisher buy-outs and other snafus too
involved to go into here) this book was never actually published.
Presumably the manuscript still exists somewhere (in Mr. Foster's
head, if nowhere else), but no one knows who will eventually publish
it and when. Or even "if", for that matter.
Hopefully, someone eventually will.