If you are flying into Melbourne, you would more than likely be landing in Melbourne's main airport at Tullamarine. The airport is located approximately 30-45mins out of Melbourne city (depending on the time of day).

 There are a few options about getting into the city. One is to take a taxi, this should be around $50-$60. Another is, if you plan to do some driving around, you can hire a car at the airport. However, if you are only really going to stay in and around the city, it's not really worthwhile, considering a lot of hotels charge extra for parking. The third option is to take the skybus. It costs approx $24 return, and has regular services from the Airport to City, and vice versa. The skybus will take you to the Southern Cross station in Melbourne, and if you like has free shuttles to any hotel in the CBD.

If you are hiring a car, the drive to the city is along the Tullamarine Freeway & then a tollway. Check with your rental company on how you are covered fro Citylink tolls. The drives from the Tullamarine Freeway to the city and on  to other major centers such as Geelong (and then the Great Ocean Road) , Bendigo, and Ballarat are quite straight forward  .  The turn offs are well sign posted and you turn off before reaching  the CBD. For Philip Island you head towards the city but stay on the toll road, Citylink, and by pass the CBD. You then continue along the Monash Freeway and follow the signs to Philip Island. All of the freeways & the tollroad are very well signposted.