Before you leave Sydney have a bullbar fitted, the roo's are in plague proportions in NSW at the moment,
Get a UHF, a hand held should be fine as long as it is a high wattage (imo 5watt),
change oil and filters get a spare air filter and a bug screen for the grill.
And give yourself plenty of time, the roads are not the best here.
Things to see.
In my local area there is Jenolan Caves
http://www.jenolancaves.org.au/
Further west i Temora
http://www.aviationmuseum.com.au/ and Parkes
http://www.csiro.au/Portals/Educatio...Telescope.aspx
On the NSW/VIC boarder there is sister towns of Echuca/Moama
http://www.murrayriver.com.au/echuca/
Then there is Ballarat
http://sovereignhill.com.au/
The list goes on, all these places I have been to and in my opinion are worth the time.
Dave