Can you buy a toucan legally in Australia?

No, it is illegal in America. (incorrect see my answer below)

The above person is actually incorrect, in most of the USA keeping toucans as pets is legal, no license required. I actually own two toucans, and have spoken to a few different toucan breeders, and the one I got my toucans from is well informed on this subject (he also happens to be an attorney and founder of the American Federation of Aviculture). I've even looked at some state laws for myself. The only state I can recall off hand in which toucans are illegal to be kept as pets is Hawaii.