This book is part of Amazon's
Sunshine Deals e-book sale, good until June 15th. So are any other non-indie titles which you might see pricedropped there to 0.99, 1.99, or 2.99 which aren't also that same price elsewhere.
As far as I can tell, many of the titles are available to Canada, at least, including this one.
Ian McDonald's a pretty good writer as far as I can tell. He was nominated (maybe won, I forget) for Hugo last year, and I think he's previously been nominated/won Nebula.
The sample has minor formatting issues, but I think I'd still pick it up at this price and notify Amazon CS of the errors.