Geoscience Australia are selling a DVD that has a mosaic of Landsat 7 satellite photos of all of Australia.
Check out http://www.ga.gov.au/acres/prod_ser/ls7 ... ic_dvd.htm for more info. There is a link to an interactive viewer on that page that shows you the Landsat 7 data side by side with the Natmap 250k mosaic. Nice.