Aborigines and Torres Strait Islanders have contributed to Australia’s military forces, though the exact numbers are not known. It is estimated that 400 to 500 served in the First World War. In the Second World War as many as 6 000 Aborigines and Torres Strait Islanders may have served as formally enlisted servicemen, members of irregular units or in support units. The Second World War Torres Strait Light Infantry Battalion alone numbered some 745 in August 1943.
The national Archives of Australia have the RecordSearch database. I highly advise you to visit this database on the internet at http://www.naa.gov.au/the_collection/recordsearch.html. RecordSearch describes over 6 million records (about 10% of their collection) – from 9000 Australian Government agencies. Every year they add hundreds of thousands of new descriptions, of documents, photographs, posters, maps, films, sound recordings and some records are digitize for easy access..
The National Archives of Australia will provide standard black-and-white photocopies of World War I and World War II service records cost AUD$25.00 per record (includes GST and postage) or AUD$28.00 for overseas purchases (includes postage, but excludes GST). Prepayment is required. (This price is current as of 2006). https://shop.naa.gov.au/servicerecord.php
World War Two & afterwards: SCMA (Soldier Career Management Agency) & Australian War Memorial.
The Australian War Memorial contains a wealth of material relating to individual servicemen and women, such as personal service records, search biographical databases, the Roll of Honour, Commemorative Roll, and various Nominal Rolls. Most of these databases are on their Internet site.