New Zealand is a fairly easy country to get around. Online you will find some cheap flights from city to city. But if you don't want to miss the sites on route then your better off travelling on ground. A car is a really good option. New Zealand is probably the cheapest country in the western world when it comes to buying good quality used cars. This will work out great value and easily pay for itself in a couple of months. If your only staying a couple of weeks then this option won't be really worthwile of course. The bad news is the train service is pretty limited on the south island and getting smaller as the years go by. But the train does pass some beautiful countyside including Arthurs Pass. The good news is that bus travel in New Zealand is actually comfortable, cheap and takes place on really good quality roads. After all Ireland, where I'm from has some of the worst roads in the world! Some of the coach companies even stop off at scenic locations to give you the opportunity to take photos or a quick smoke.