Yo! The Mighty South Aussies represent. I'm from Adelaide but been in north merika 2 years now, came here to do the things you cant in Australia.
Australia doesn't have the same scene of kids pissed at the social system and turning to the streets cos it's not as fucked up in Australia as over here. Hell, that's a good thing. Having said that there's still a lot of punks, travelers, adventures and DIYers in Adelaide and nationwide. You'll find them if you seek them. PM me if you've really looked and still at an odds
From all accounts hitching is very possible in Oz - maybe more so on the eastern seaboard. Riding freight is much tougher, dangerous and illegal back home than it is in the US. Also not impossible, I personally just never got around to it. Do a stp search and you'll find the right people to ask about specifics. I look forward to riding Brisbane to Melbourne if I make it back home, but I can wait - I'm having too much fun on US trains!