I've looked into Air Passes before, but I ended up buying tickets individually
from Jet Start, Qantas or Virgin blue. Prices were pretty close if not cheaper
but I had lot more flexibility.

Only issue could be the luggage limits. QF will give you higher limits along
with the trans-pac QF flight.. limits are much lower on Jet Star and
Virgin blue.

Sites: (use the Australian portal.. it gets cheaper in most cases
but your CC might be charged extra 2-3% foreign transaction
fees)

http://www.jetstar.com/au/index.html
http://www.qantas.com.au/regions/dyn...fier-region-au
http://www.virginblue.com.au/

And its simple to buy multiple oneway tickets without outrageous charges.