✔ 最佳答案
Actually it is very common to travel by driving around. However, it will take you some time if you are not familiar with the places. So local tour is a good choice. Some of them do not quote their price on the website and they might have some trips on discount in a short period of time.
If you choose to book it online, your place should be secure after you have paid online. If you choose to book it later, you may have a surprise in the tour fee but the tour may be fully booked.
I would suggest you to visit some websites before making any decisions. e.g.
http://www.tourism.australia.com/
http://www.visitmelbourne.com/
By the way, about GREAT OCEAN ROAD, if I were you, I definitely will join the local tour instead of driving cos you can look around the beautiful view rather than concentrate on driving on that hard road!
參考: personal experience... i have been to great ocean road.