Sandy Point is the goods this weekend. Windguru has Wednesday, Friday and Saturday looking *really* good.... suggest bringing a speed board, but you didn't hear it from me...

If you cannot make it down that far (from Melbourne...), St Kilda, Elwood, Ricketts Point, etc will all provide some good bump'n'jump.
I'd suggest at least a 3/2mm for wetsuit... water temp is 18deg, but within the next few days, I'd expect it to drop to 17deg.