Thanks for the comments
I've been playing around with the Nook tonight, the Kindle was actually fairly easy. The problem I'm getting with the Nook (and I think it could be the same with the iPad) is that when I'm trying to fill out my payment details it's asking for my tax number. I've tried researching this, and most forums are saying that it's because it's an American based company that has to pay American taxes, so the IRS make them find out people's social security/tax numbers in order to bill them!
That's all well and good for American people, but doesn't help me! One Australian guy said in a forum that it's possible to get an international number but it's a long form and takes 8 to 10 weeks to process! So, the Nook's on hold for the time being.
The iPad, I'll give that a try tomorrow but I've got a feeling it'll be the same thing. Can you get a Kindle app for iPad?