Far North Queensland :
www.seabreeze.com.au/weather/wind-forecast/qld-far-northCairns/Port Douglas both have easily accessible kite spots but you will rarely get clean winds and you almost always get much less wind than the forecast when you're along the coastline. Depending on your expectations, your skills and your equipment, kiting can get frustrating at times in those areas, you have to be patient and expect light/gusty days even with lots of green arrows on the forecast.
The more North of the Far North Queensland you go (or if you go on off-shore islands) the better the winds will be, depends how far you're willing to travel, your transportation/camping setup, your budget, how much time you have, etc.
The BEST winds are really around Cooktown or North of Cooktown, or around Lizard Island and such, those places have the most reliable, strong and steady trade winds by a long shot, but not easily accessible...
Christian