Australians can register as an organ donor here.
Australian's Donate has the role of promoting organ and tissue donation throughout the country and to aim at having the practice considered the norm rather than an aberration. My personal opinion is that it should be an opt out situation rather than opt in. That way people who object for religious or other lifestyle reasons would need to register not to be a donor rather than the other way around. In a lot of cases time is of the essence when harvesting the organs or tissues so allowing doctors to move quickly has the potential to both save or improve the situation of many people on the organ donor waiting lists.
Read the stories of some of those who have been recipients here and make up your own mind. And so I am not accused of failing to practise what I preach I am registering with the Australian Organ Donor Register.