Something that may be of use to people thinking of coming over is the following websites, that give an indication of the cost of housing
www.realestate.com.au
www.domain.com.au
Sydney housing has always been expensive, and not working there I could not recommended any suburbs. Melbourne's airport is north of the city, so start looking at Tullarmarine & surrounding suburbs if you want to be within 20 minutes drive. Brisbane's airport is fairly close to the city and some fairly expensive suburbs - try Clayfied, Hendra, Toombul, Northgate etc.
In Brisbane (where I work) you'll see that a 3 bedroom house with double garage and 600 sq. m's block in the suburbs I mentioned can set you back anywhere from $350,000 to $700,000.
The realestate website also lists rental properties, but be advised there is a recognised rental shortage [5% vacancy] and potential renters are often in a bidding war for the house they want.