I'm also Aussie. 95% of my sales this year has been to the USA, Germany, UK. Shipping and payment methods were a headache, but it was the issue of getting onto the best method. I don't think any method is absolutely foolproof, but to their credit, Australia Post haven't let me down yet. Everything has arrived, and fairly quickly. (Been about the same - about 5-8days to most places.) I use First Class Air Mail, I insure everything for their actual listed value and declare exactly the contents.
Reg's story is especially important - post 9-11 especially, expect that your package will be opened. And any infringements acted upon.
The issue of payment methods has been the bigger problem, given the proliferation of scams and shonky operators just north of us.
As far as I am concerned, sending, receiving in locations like UK, Australia, shouldn't be any problem as long as you comply with local laws. Of course, it is up to the person ordering to ensure that their purchase is legit in their locality in the first place. Jason.