Ace,
If you go to many of the bike stores they may have a small assortment of 2nd hand bikes which have been traded in when people have upgraded. Also for 2nd hand bikes, have a look every couple of days on the triathlon WA website (
www.triwa.org.au) and go to chat site, there are usually a few bikes for sale there.
For new bikes, most bikeshops have basic brands which start at about $800, but realistically you would need to look at spending at least $1100 to get something that won't fall apart in a few months.
hope this helps, and good luck on race day. I will also be flying the flag for my company.