You could look at the new "Earth +" Card (
www.earth.com.au)
"
* No Westpac foreign exchange fees for overseas purchases
* No Westpac cash advance fees on overseas ATMs
"
I have no experience with this new card, so check it out carefully. Comes in MC and Amex flavours.
I'm not even sure if there are standard exchange fees applied. There really isn't much data available on the card, but i think it could be one of the best for overseas purchases.
Make sure you read the fine print carefully.