It's a great idea.
Been here for 6 months now and have loved every day of it.
A fortnight ago my girlfriend and I did a pretty big road trip from Perth to Sydney.
http://emigratingtooz.com/
Some interesting things to read on that.
www.airasia.com will probably be the cheapest flights you can get. They fly from London to Perth, Brisbane, Melbourne and Darwin.
In regards to money, the more work you get over here the better. The cost of living is high, but so are the wages. Supermarket job earns you around $20 an hour.
Feel free to ask questions