I just discovered a great way to get Audio Books. www.audible.com
I'd been looking into this because my job takes me on a lot of long drives . . . between 90 minutes and 3 hours, often there and back in a day. Staying awake through 6 hours of driving in one day can be hard, even with a trusty can of Red Bull in the car. The best way I've found to stay awake has been listening to audio books.
The first thing I started off with was the BBC Radio play of the Lord of the Rings. That somehow let me drive a lot further without getting bored or tired.
After developing a taste for the audio books, I started trying to find out how other people were buying them, rather than just going to iTunes (which is definitely the most convenient). Audible popped up instantly, with a lot of good reviews and cheap prices. I've signed up for a "too good to be true" deal, which is a 3 month subscription for about $8 a month which gives you one free audio book a month plus a discount on any others you may want to buy.
If books on paper is more your thing, there's bookdepository.co.uk This site sells books in GBP, which when converted to Australian dollars makes them super cheap . . . and to top it off, they have free worldwide shipping. If only someone in Australia could actually compete with those prices . . .