I think I might be able to explain a little of this:
According to the Sydney Morning Herald, Australian bookstores have been denied access to sell the book, not because of any government ban, but because the US distributor has decided that it will not sell the book outside the US or Canada. The distributor, Ingram International, will fulfill existing orders, but will not accept any more orders.
This is a very curious story. What is not said but is left implied is that the most controversial aspect of the Tom Cruise story is his adherence to the Church of Scientology. It seems that the Church came to some sort of legal arrangement with the distributor.
It\’s entirely possible that other of the explanations offered (like the differences in libel laws) are true. But what I suspect has happened here is a result of the way in which publication rights are handled.
For an English language book (other languages work in the same way, but with different regional distinctions. Thus a French book might distinguish between Quebec and Metropolitan France, a German one between Germany and Austria) the world is divided into various territories. What actually gets distinguished varies according to the popularity of the title: Harry Potter books will make finer grained territorial distinctions than will, say, Crap Towns in England.
But the publisher buys the rights to publish a title in a certain territory. The US say. Or Canada (usually separated because of the spelling differences in the language). Or the UK: sometimes Australia and New Zealand are lumped together, sometimes separated. Now, if you own the rights in one territory and no one else has bothered to buy the rights in those others, then Ingram (and Amazon etc) will happily ship copies of your version to those other territories.
But if someone has indeed bought, say, the Australian rights to that book then Ingram should not ship US copies to Australia (whether this is a Gentleman\’s Agreement or actually a legal requirement of copyright I\’m not sure. But it certainly happens with US and UK versions of books. Or rather it can, if the relevant publisher makes the purchase of those territory specific rights known to the distributor).
So if you were the Church of Scientology and you didn\’t want people in Austalia to read the book, the easiest way would be to go to the US publisher and negotiate to purchase the Australian subsidiary rights. Given that it\’s unlikely to be a great best-seller, a few thousand dollars would do the trick.
( As a not very relevant example of foreign rights pricing, I was once offered the Russian language rights to Hitchhikers\’ Guide to the Galaxy for $500, no further royalty.)