Do you mean literally on the reef, or just in North Queensland?
In Cairns there's Green Island which is a $50 ferry ride. The way the wind has been honking lately though you can just turn up at Yorkey's knob and get a decent session in.
I was up at Cape Trib a few weeks ago, and there's a few local kiters there (one works at the camping ground) who can give you some info. It can be technical at low tides, but there's generally plenty of wind. I reckon Thornton's beach about 15 K's south of Cape Trib would be awesome, but I haven't kited there yet. The undiscovered (ok then, slightly discovered) secret is Wonga beach north of Port Douglas, and even Fourmile Beach at Port douglas is great. Brett at Windswell also offers trips, downwinders and reef sessions. I think he has a banner on the North Queensland windspeed obs on this site. Here is his site
windswell.com.au/ If you really want to do the genuine reef thing, then ask around at Yorkeys knob about Bill who takes a boat out to Vlassof if you get a crew together. Pictures here
www.seabreeze.com.au/gallery/gallery.asp?imageid=982&text=vlassof
