If you play a sport you could apply for a position as an umpire (i.e. for netball, hockey etc..) I'm pretty sure that even if you don't play hockey you can take a two month course and become an umpire.
Or if you can swim you could apply for a pool lifeguard position ( my friend has being doing this since she was 15)
Alternatively you could look into the Army reserves, I think they only require one day a week minimum of work and they have a variety of positions - you'd probs have to look into that though..
I'M not sure about I.T jobs, I do have a friend whose brother was into I.T and he managed to get a part time job at his uni's I.T department. If you're not too bothered about what you want to do you could check out
http://melbourne.gumtree.com.au/ for cleaning, waitressing and lots of other opportunities.
Don't worry about experience, even if they say 'experience preferred' you can still ring up and give it a go. In fact my sister has no experience in massage therapy at all and she got two massage jobs on gumtree. Gumtree has been a gold mine for us, so check it regularly and you'll find something for sure!