If you do not have an Australian or New Zealand passport, the Department of Immigration and Citizenship provides information and downloadable forms for various types of visas.
Temporary (Working Holiday Maker)
If you are aged between 18 years and 30 years, you may be able to apply for this visa which allows you entry into Australia for a limited time, with the opportunity to work, also for a limited time.
Permanent (General Skilled Migration Program)
This program is to assist people wanting to migrate to Australia, who have qualifications in a profession that may be required in Australia.
The Australian Skills Recognition Information (ASRI) provides skilled occupation information, relevant to radiography, sonograpy and radiation therapy.
Radiographers are currently listed on the MODL, and if you meet the required assessment and examination standards set by the Council of Occupational Therapists Registration Boards (Aust and NZ) Inc, the information provided may be useful to you.