Not sure if this is available to you, but I found that I got a really reasonable rate of exchange last week, by going into westpac and doing a cash advance on my US account which has a Visa Check Card.  It worked out at $1.0335 AUD for 1 US (not bad given the exchange rate on my desktop was $1.04).  It came out of a checking acct. I have in the States.

Give Wire transfers usually cheese you out of at least 3% on the offical rates + usually have a +/- $20 upfront fee, I reckon that's the go for me.