Events: 2x2, 3x3, 4x4, 5x5, oh, bf, pyr, mgc (8)
Competitors: Preferably 12 local to NSW interested and able to attend (then announce), more intestate would come.
Venue: Having a high school or university support you would be good. If they sponsored it as an extracurricular activity for students and covered the cost of venue hire and public liability insurance then it becomes a lot easier.
I could try to promote it as an RMIT event if you wanted to hold it at some shopping centre or public venue with $20 million of public liability insurance for free. Then again, if it's in such a public venue in Sydney, Crown and Andrews might be interested in supporting you.
Equipment: 4 stopwatches, 4 displays, 4 timers, pens, 200+ scorecards, regulations, scrambles(I can provide)
Freebies: bags and lanyards (from Seven Towns), 50 holders, 50 inserts (printed with names) AU$66
Prizes: stickers from cubesmith? AU$34
Certificates: 3 per event ~ AU$60
Total: ~ $160 (assuming the venue is free)
Registration fee could be $10 (with 16) to cover these costs. I could fly up for free to delegate but may need some kind of accommodation (I've a sleeping bag

).
It's difficult to say how many events there should be without knowing how many competitors there are and what events they'd like to do. Once you know roughly what events people are doing, you can reschedule events, but I wouldn't recommend having too many at the first competition.
If there's any help needed, just let me know. I can try to get in contact with UNSW and USyd...
Tim.