Personally I think "early autumn 2012" (by which I assume you mean northern, and not southern autumn) is too far out to expect to see discounting on business class fares to Oz, unless you want to lock in a Circle Pacific fare, which may or may not (I suspect not) offer much in the way of savings with a US origin point.

In which case your options are (a) to keep shopping, patiently, or (b) go for mileage redemption tickets (and if AA miles are to be used, then the AA board is the right place for inquiries/discussions.)

However I'd also put the Oz trip in the context of the rest of your anticipated 2012 travels. Are you doing other international trips that might lend themselves to adding Oz into a year-long ticket? For example, if you're traveling to Europe or the Middle East, you might look at an RTW itinerary originating in some less expensive country (e.g. Israel, Egypt, Jordan) that allows you to include Oz as part of the itinerary. Might require more long-term planning than you'd like, but the potential for major cost-savings is there.