Pricey.
I've found the USB 2.0 Extension cables at monoprice.com work well and are reasonably priced. I've used the 10m ones extensively. They also have 15m, 20m and 25m extensions. I've found that just about everything at monoprice.com is high quality at a no nonsense price. I'm not sure if they ship down under though.
http://www.monoprice.com/products/su...02&cp_id=10303