Thanks Jason. I have set it up using charges tab of eCart, but can change it to shipping instead if that works better.
Your rule and calculation is not quite what I need, as I have to account for locations and quantity. I guess that's by using session variables, right?
Here's the shipping costs:
Australia - 1 item = $7
Australia - 2 or more items = $10
New Zealand - 1 item = $12
New Zealand - 2 or more items = $20
International - 1 item = $20
International - 2 or more items = $35
Local pick up = $0