Definitely do the whole east coast, especially Queensland which is beautiful. (Top of Queensland down to Melbourne). I agree that you should travel to Queensland/Northern NSW in the winter as it is still warm up there during this time, compared to Melbourne which is freezing and snows in the mountains. Come down to Southern NSW and VIC in our summer (Dec-Feb) the weather's great then. You have to do the Great Ocean Road, then continue on to Adelaide, it's awesome.

As for work it's pretty easy to pick up work on farms, but be prepared to work really hard especially during the summer as it gets ridiculously hot.

I would also advise getting a Lonely Planet book as it will give you all the information that you need.