Do you have an idea of where in Australia you wanted to study? Or why exactly you want to study in Australia? The reason I ask is because your motivation for going will rule in/out various unis, and for an international student funding is largely (to my knowledge) dependent on which uni you're heading for.
For example, if you want a more 'prestigious' Australian uni, you may want to consider ANU (in Canberra). If you want to go for the lifestyle/weather/
beach then maybe Griffith is for you, and ANU would be out of the question (awful weather and nowhere near the ocean). If you want prestige and the beach (and city life) then Uni of Melbourne or Sydney might be good choices. I'm from Perth and went to UWA, which I loved, but Perth/UWA might not be the right fit for everyone - it's allegedly the most isolated capital city on the planet.
Funding may also depend on what you want to study. Australia's a big country (as I'm sure you know) and things very state to state, as well as between unis. As a rule though, I'm not sure that funding opportunities for an international undergrad would be great at any of the unis (but I don't know this for sure).
Once you've narrowed down what you want to study, and what you want out of your Aussie uni experience, it might be a bit easier to work out exactly what your chances of a scholarship are, and what the application process will entail. If it's anything like the process for Australian undergrads, they'll look more or less exclusively at your marks and academic achievements - but extracurriculars/volunteering may help with the scholarships.
I hope this helps a bit. If you have other questions, feel free to ask