[Heritage Victoria] - "... home to the Victorian Heritage Register which lists the State’s most significant heritage places, objects and historic shipwrecks protected under the Heritage Act 1995. It's also home to the Victorian Heritage Inventory which lists all known historical archaeological sites in Victoria."
[City of Melbourne] - i-Heritage is the City of Melbourne's online database of heritage places. It provides details on individual buildings and contains properties included in conservation studies.
A guide to Victorian house styles [Heritage Victoria] - "...describes the main styles of houses still present in Melbourne, including their cultural background and key exterior and interior features and colours."
A good starting point for your research, the ADB is "... Australia's pre-eminent dictionary of national biography. In it you will find concise, informative and fascinating descriptions of the lives of over 12,000 significant and representative persons in Australian history." The ADB is produced by the National Centre of Biography at the Australian National University (ANU).
"This site tells the story of modernist residential architecture and the development of Canberra, through profiles of significant Canberra houses, architect biographies and articles about architectural styles and heritage issues."
This site provides information and images on contemporary and historical Sydney architecture.
(Via Internet archive - 5/4/20 unable to access site directly)
"This digital archive of Queensland architecture offers a wealth of information on the region's design history. The archive was originally ... focused on the period 1945-1975 ... [but it is] now expanding to include earlier and later periods."