Melbourne is quite a small city. If you are on a self-managed trip, you might finish the entire city in 2 days. The greater victoria might be an interesting point of interest, some of them is Dandenong, Great Ocean Road, and Philip Island. I would reccomend the last one for the experience you won’t get elsewhere: The Penguin Parade!
Philip Island (Website: http://www.penguins.org.au/) is located around 2 hours by car from Melbourne. It host 3 natural parks: The Penguin Parade, Koala Conservation Center, and the Churcill Island. The option I would reccomend for visit is to rent a car and spend 1-2 night on the island, or take a guided tour, like what we did.
There are a lot of tours offering a day trip to Philip Island for AU$100. Some of them offers half-day trip for AU$70, but my recommendation is to take the full one, because of the experience given. We were taking Australian Pacific Tours (APT, website: http://www.aptours.com.au/). They pick us up from our hotel take us to their head office for us to settle the payment, and then we hop back to the executive bus, which took us to Phillip Island.
The driver did a double job as your tour guide. He tells what is on your left and right while driving, through a headset connected the bus sound system. We go through the beachfront estate of St. Kilda, to the country road, and stop at Warrock (meaning large water in aboriginal language). In this farm, they have Kangoroos, Wombat, and also a Phoenix. There are a souvenir shop, which I found a jacket for AU$50 :D.
Our next stop is the Koala Conservation Center. We are given opportunity to see the sleeping Koala (They sleep 20 hours per day. You will do the same if you only eat Eucalyptus leaves :D). If you’re lucky enough some of them will awake and sit close to the boardwalk, where you can take some nice pics.
Next stop is the city of Cowes, the only city in Phillip Island. They serve wide range of food for your dinner. After dinner, we continue to the fur seal viewing point, which is actually the only part of the tour which is not worth it.
The main show come after the fur seal, where we are taken to the penguin parade show. The penguin will do the ritual of thousands year, where they came back home after searching for food right after the sunset.