Austrian Pilot, welcome to Australia from a fellow Austrian-born pilot
Do a search here, the schools at Archerfield have been discussed quite recently. As a private student you probably don't want to join one of the sausage factories, so talk to Sunland (great Cirrus planes), Gil Layt and the RQAC, and take your pick.
Feel free to PM me, I'm based at Archerfield and would be please to show you around and help out if I can. When are you coming over?