If you are going to Melbourne for the New year's eve and also want to shop for motorcycle accessories, Peter Stevens on Elizabeth street is the place to go. It is downtown, which is a pretty compact area and every street is within walking distance. If you are looking for some spare parts or frame sliders, it is better to order as soon as you land there so that you get them in 4-5 days. Oz is very expensive as compared to the US, so choose your merchandise with care.
I went to Sumoto too on Boundary street, but that turned out to be a waste of time as far as accessories went. Unless checking out how a CB 400RR looks like is your idea of fun.