Joao,
Mate gold is everywhere in Australia, it just occurs in large patches. Every state has goldfields, some richer than others.
Heres a good site with an overview of some of the states, follow the links on the left of the page:
http://www.treasureenterprises.com/...ospecting_tips_locations_within_Australia.htm
Have a look on the forum here:
https://prospectingaustralia.com/forum/viewtopic.php?id=2232
https://prospectingaustralia.com/forum/viewtopic.php?id=2398
A good starting point for your Australian adventure would be Cairns, its surrounded by goldfields, they also got wolfram and tin. Cairns it was originally established as a port for the goldfields, heres is some research I did when I arrived here for work back in April:
https://prospectingaustralia.com/forum/viewtopic.php?id=6112
If you come to Queensland I can take you to a few good spots.
Cheers,
Grant