Mic85, other posters have mad mention of the costs and difficulties you will face along with weather and you really need to take some notice of what is being said for the weather.
Driving north from Adelaide, you will soon be getting temperatures approaching if not exceeding 40C and whilst sitting in an air conditioned car may sound fine ( as long as the airconditioning does not fail ), you will not be enjoying too much seeing what you can see and even short walks will quickly leave you dehydrated.
Even with airconditioning working, you will find a hot sun through a window can have a cooking effect.
People have gone into outback areas and died through dehydration, it no place to be driving into during summer for a touring holiday, not too many Australians doing it at that time of the year and as for an easy drive as put in #9, just get the idea completely out of your head.
I see you list Italy as where you are from and you will likely have never experienced anything in Italy like what inland Australia is in summer.
Would you jump out of a plane at 25,000 feet to aim for a relatively very small catch net?
I think not and so do revise your thoughts.
As for camping in areas around the coast that is fine though as others have indicated, you are coming at peak holiday time when many Australian families are taking holidays from work/school and many do go camping to popular coastal destinations and so you need to get a plan in place based on what towns you can book into - use a site like www.travelmate.com.au to get information on distances and routes to plan a route and then google for caravan parks for different locations at which you will stop. Maybe you allow 300 - 400 - 500 km. a day travelling distances.
But just Forget about going inland too far and do remember that we drive on the opposite side of the road in Australia so be very careful when driving here.