Tracing Greek Australians in the National Archives
The National Archives of Australia includes a section on their website entitled "Groundbreaking Greeks: Tracing Greek Australians in the National Archives".
This page includes a history of Greeks in Australia:
Trading on talents
Building up business
There are also links to "Collection references" related to Greek Australians.
And last, but not least, is the section titled "How to find records about family members".