molly molly,
You can purchase study guides here:
http://www.theaviatorstore.com.au/category82_1.htm (CPL)
http://www.theaviatorstore.com.au/category83_1.htm (ATPL)
This place seems to have practice exams available on-line:
http://www.bobtait.com.au/cyber_exams_net.htm. They're not free, though (sorry!).