Melbourne is headed in the same direction Sydney has, they reach a point where the cost to profit isn't worth developing the surrounding land, so it will begin to spike.
Within 10km of Melb CBD those ring suburbs tend to be slightly pricier, but also have a higher increase in their value each year of somewhere between 7-10%.
If you don't mind living further from the CBD, there's the south east peninsula which is about 40km out that has reasonable prices and also some fairly strong growth of about 6-8% each year. I'd look at somewhere by the coast down there for something that would be highly desirable if you're selling it down the track, plus its usually fairly well serviced by rail and actually looks 'nice' to live in.
There is also the north west up towards Sunbury about 30-40km out of the CBD, not as well serviced by rail but it has been developed recently and prices are still low-ish for now. It is kind of ugly out that way though (ie: blisteringly hot in summer and cold in winter, plus its not exactly pretty outer suburbia)
The big-ticket suburbs of Melb with median prices of 1.5 to 2mil and the more traditional blue-collar inner city suburbs ranging around the 0.6-1mil aren't worth it at the moment in my opinion, they have very low growth rates annually and don't seem to move up in price very much. They do rent for reasonable to high prices and are in good demand for that, so that may be something to consider as an investment property to sit on.
Reason I mention the indexing is that while you might buy and live there for some time, maybe later for various reasons you decide to punch out and sell is to come out of the whole thing with some money in your pocket after paying off the mortgage so you can start up again somewhere else or go do something frivolous with the cash.