whenever said...
One last word. Just saw online that you can buy the new 40D for only about $300 more than the 400D. Get that instead - rated for twice as many shots, solid body etc. etc. One store online is http://www.d-d-photographics.com.au/index.htm I assume they do duty free.
of course there is also the option of going Nikon. The D300 is a probably a better camera for money. Compared to both the 400D and 40D. Given that you still need to buy the lenses you still have a choice as to which system you want to buy into. While you can always switch at a later stage you will have to be prepared to take a bit of a hit when it comes to resell value.
Personally I am using Canon gear for work because of the support they offer to professional photographers and the simple fact they are the only company that offers a DSLR with a fullframe sensor capable of producing images close to what you will get from a medium format camera . If I was to buy a camera for personal use only I would probably consider both Nikon and Canon.
Regarding your GST refund questions take a look at this page:
www.customs.gov.au/site/page.cfm?u=4646 .
They have the most current information on this subject.