Q: Can I purchase an iTunes card in the UK for use in Australia?
A: The short answer is no—at least not for use with an Australia iTunes Store account. iTunes Store Gift Cards are restricted for use by accounts in the countries in which they are sold, so a UK iTunes Gift Card can only be used with a UK iTunes Store account. That said, iTunes does use any kind of geolocation technology to enforce account access, so you could theoretically setup an iTunes UK account with a UK iTunes Gift card and use it from anywhere in the world. However, to purchase content beyond the value of the gift card, you would need to provide another method of payment such as a credit card with a UK based billing address.