Melbourne remains the pinnacle of Australia's street art scene. Hosier Lane is a popular favourite with tourists and wedding parties (along with the Parliament building, fuck knows why you'd want that in your photos, but that's marriage for you).
Outside of Hosier Lane, there are a number of places where one can see some spectacular street art. Keep your eyes peeled anywhere you go within the inner city for stickers like This is a heavy product, paste ups and stencils.
For those with a real interest, it is worth spending a week travelling to the end of each train line to see the graffiti along each of those lines. There is a distinctive hipness bump in the direct inner city that gently changes to the more traditional piece work as one gets a couple of stations out. As one hits the outer rim of existence on some of those lines one is more likely to see younger, and in some ways wilder, tagging and graffiti - practitioners getting ready for the big league in town. The evolution is really something to see. It's quite magnificent.
Culture Jamming was quite popular in the late 90s and early 2000s, with Malvern Station of particular note. For three years it's billboards were unsellable - changed within hours of having been replaced. Heavily influenced by an anti capitalist mindset, and situated in a wealthy suburb, it was a morale boost for all those that travelled through it.