The webmaster who's breached your copyright is answerable to the law of the country where you conduct your business. If you are in the US, you're covered by US law and any disputes should be settled in a US court.

[copyright.org.au...]

The webmaster who's breached your copyright is answerable to the law of the country where you conduct your business. If you are in the US, you're covered by US law and any disputes should be settled in a US court.

You have this completely backwards.

There are two things that determine the jurisdiction of the case - The location of the infringement (Australia) and the domicile of the infringer (also Australia). Where the work is copyrighted only makes a difference whether the work is protected by Australian law due to treaty (the Berne Convention).

Even within the United States, if someone infringes your copyright, you have to sue them in the district where *they* reside. If you are in California and they are in Florida, you have to file the suit in the court with jurisdiction over the portion of Florida where they are domiciled.

Suing Australian citizens in the United States would do you no good, because, US courts would have no way of enforcing their rulings. The courts won't waste their time hearing a case where the ruling wouldn't have any effect.