I assume you are a medical graduate from a country other than Australia or New Zealand. I suggest you visit (google) the Australian Medical Board and read the section on International Medical Graduates (IMG). It contains sufficient information for you to follow. Should there be more specific questions you wish to ask, please post your question again.

Just to clarify the terminology used - in Australia, the term residency is different to that of the US. A medical graduate is required to work in a hospital as an intern for a minimum of 12 months in medicine and surgery (formerly intern was called Junior Medical Officer or junior Resident. Ati Radeon 9550 / X1050 Series Update here. Only after completion of 12 months os satisfactory supervised service before one is able to be registered legally as a medical practitioner by the Australian medical board), subsequent to that, further training could be gained as a senior Resident in other areas such as child health, obstetrics and gynaecology, anaesthetics, critical care, various branches of medicine or surgery. Should one wish to become a specialist, one applies for a trading post in a particular specialty, and work as a registrar. There are a number of exams to pass in the specialist colleges.