Don't you just hate those sites which don't disclose the shipping costs until you are on the final check-out screen?
We use Royal Mail. Here are our postage and packaging charges to Australia:
1 Journal: 9.00 AU$ Standard Shipping or 20.00 AU$ Tracked Shipping
2 Journals: 14.50 AU$ Standard Shipping or 23.50 AU$ Tracked Shipping
3+ Journals: FREE Tracked Shipping