I never saw anything even approaching YC while I was in Syd. Two questions:

1) What's stopping you from moving to the US?

If you wanted to, you could be here on an effectively permanent basis in a matter of weeks (we have an unfair advantage in the form of the E3 visa, a version of the H1B for Australians). Get in touch if you'd like to chat about this.

2) Are you making the most of a community which isn't formalised/mature enough to support a YC equivalent?

There are some real kickass entrepreneurs in Sydney, who I'd say are more approachable and helpful than their equivalents in cities with a more mature startup community. Get in touch for some names, or just show up to Silicon Beach drinks and talk to as many people as you can.