Flying an aircraft in Australia on your Canadian license is fairly simple. You will have to do a checkout with an Australian flight instructor and they will issue you a CV (Certificate of Validation). This will validate your Canadian license and then you can rent or borrow Australian airplanes and fly day VFR.
There are no exams to write or other requirements. Since any school or other rental agency would probably require a check flight anyway, this requirement is not very onerous and should add no real additional cost to flying there.
There is also a security clearance requirement to get a license in Australia – it is suggested that you apply for that at least six months in advance. Check the CASA website for specifics on the security clearance procedures.
Have a look at the general CASA website for more information as well as our sister organization there – AOPA Australia. There is good information on the Air Safaris International website as well.