I did the Oz thing in 2001 - I purposefully went on my own as my mate tried it and you never get to do all the things you want to do and it can put a strain on your friendship.
Basically rock up to a hostel get settled in and in the evening at the bar simply say to a large group "Hi just got in today , do you mind if i hang with you guys/girls"
travel light , be prepared to exist on basic foods (smoothies n rice etc)
if you are going to backpack i can reccomend something like this
http://www.webtogs.co.uk/Pacsafe_Pacsafe_85_Backpacker_517-2433.html?PID=pg&utm_source=Pricegrabber&utm_medium=pricecomp&utm_campaign=Pricegrabber&utm_term=Pacsafe85BackpackerIn 2 months i only needed it once (dodgy hostel , middle of sydney on new years eve so was limited in my options) however the peace of mind it gives is well worth it
I used this site as a guide
http://www.artoftravel.com/If you can when you get there open up a bank account to stash your money in as opposed to carrying it with you then when you need money just go to a cashpoint.