Hi Paul,

You don't say what you like to do when you travel?

Or how you travel, where you stay.

Now, me, I'm a camper.  I plan to rent a campervan.  BTW over in Oz 'van' often means some kind of wheels or travel body (like truck camper) without an engine.  Drives me snake that does.  To me a van has an engine.

A carvan is a trailer set up for living in on the road, ie. 'travel trailer' to  N. American, for all that in the UK caravan means the same thing to a UK resident as to an Aussie.

& do you like cities, tourist highlights?  Or small burgs and the places which really make Oz different ?

I'd visit your local bookshop and get your paws on a travel guide to Australia, like a Fodor's, Frommer's, Lonely Planet.  Here in Canada, the big bookstore chain, Chapters.Indigo has some kind of set up with Frommer's.  I've got a 2012 Frommer's on order for me and a 2004 Lonely Planet guide from a friend..

Also, I'd check out weather.  April and May are the fall of the year, getting cooler - not that parts of Oz ever get cool.  Some coastal sections never see frost. 

& how are you going to get to Oz.  Me, I'm travelling by airmiles.  I don't have all I need yet, but I'm getting there.

Like Aart said, a broad question and hard to answer in a few words, a few things to keep in mind, you'll only see a small bit in two months and the distances between places is huge so pre plan carefully to get the biggest "Bang for your Buck".
On the east coast it is touristy and busy, rural western NSW and Queensland are more the real Oz if that's what you're looking for, West Australia..... a long way between drinks.

pd

I would suggest you go here;

http://jobsearch.gov.au/harvesttrail/default.aspx

to plan for harvest work an travel.

HTH