I don't know about in Melbourne but with DD we had one done in Ballarat at 26 weeks. We needed a referral from our Ob and it costs us about $190 (we got a DVD as well as pic's) and because it is not a standard scan you cannot claim back from medicare. I'd find out from the U/S place where you will have your 12 & 20 week scans at if they do the 3D/4D scans as well.