There is a now an airline watchdog in Australia. The Airline Customer Advocate (ACA) offers passengers a place to take their customer service grievances with the hope that the airline will be named and shamed.
If you have flown with Qantas, Virgin, Rex, Tiger or Jetstar, placed a written complaint twice to the airline with no satisfaction; then you can take your complaint to the ACA. They will assess your complaint and possibly report on your issue.
If you have a complaint visit the Airline Customer Advocate to lodge your complaint.