You're incorrect. 16x media has been available (at least online) since at least 3rd quarter of last year. Admittedly some brands such as 16x Verbatim is still hard to find in bricks & mortar stores as they're still clearing excess stock of 8x media, but online it is easily found.
All your BIG W, K MART, Target, Office Works stores etc are selling TDK branded 16x media (though I'm not personally fond of it)
Do a search via google or via www.staticice.com.au with an appropriate search term such as "Verbatim 16x DVD+R" and you'll find sources to buy from.
www.pcx.com.au just started listing 16x Verbatim printables in both formats. Look a bit harder and yee sha'll find