I got the new one from Amazon for US$35 (+ shipping, and I paid for express - about AU$80 all up) - arrived Tuesday this week - I am already well in to it - a great read (but the spelling is USA eg. liter, and it is a different cover to the UK version).
Also check this thread:
Trevor Legate's New Book! - Trevor will get you a signed one for less than AU$200.
Craig: Cheap one is discounted price - old one is even more expensive (if it can be found).