Government departments and agencies produce a lot of grey literature, including
Many of these are listed on the department and agency websites.
Australia.gov.au links you to the right information and service on around 900 Australian Government websites, as well as some state and territory sites.
Libraries Australia: Recent Australian Government Publications - a series of text files that list new government publications that have been added to the Australian National Database and published in the previous 2 years.
Check CSU Library's Australian Government Information guide for more links.
CSU Library also holds a microfiche index of Australian Government publications 1961-1998, that you can search manually.