As above, the Q's at the back of the chapters in the Thom books are useful.
I'm surprised the confuser is out of print! It's a useful tool for that final knowledge testing/exam technique preparation prior to the exam, after reading the books etc......
Have you tried ebay for second hand copies? Has anyone at your club got one they no longer need that they can lend or sell you?
The airquiz website is good, very reasonably priced and if I remember correctly the questions were fairly similar in style to the real thing.
Good luck!
B