I was very surprised about the one big language 2/3rds of Australia.
The South Australian (state, not region) museum mentions 46 languages in south Australia.
www.samuseum.sa.gov.au
This article repeats the 46, and mentions that each tribe had its own language, but that they were related.
More than 50 Aboriginal groups occupied what became known as South Australia in 1836, each having a distinctive language and defined territory.
sahistoryhub.history.sa.gov.au
The wiki thread on the Pama-Nyugan language group (which seems to be what that language represents)
en.wikipedia.org
mentions that it comprises 306 languages, some of which are hard to group together, others are as similar as to near-dialects on par with the differences between the Scandinavian languages. That suggests grouping them together is only valid if you group Swedish and Danish together...
If you want a breakdown of where those languages should go I'd suggest contacting this person. From the header they appear to have such a list, but you would need to discuss how you were intending to use it -
https://anggarrgoon.wordpress.com/2...ages-were-spoken-in-australia/#comment-136716. They are the source referenced in wikipedia.
They were small, but very historically and economically significant. As the only location that nutmeg and mace grew the VOC used them to monopolise the trade in a single spice. That was the same tactic they later used on cloves, but doing it with nutmeg and mace so early gave the VOC a boost that allowed their domination of Indonesian trade.
museum.wa.gov.au
The dark history of the nutmeg trade: how the VOC committed atrocities in pursuit of profit on the Banda Islands.
medium.com