Ok, Okinawa is a bunch of islands south of Japan, east of Taiwan.
The cheapest way might be to actually get there from hk/taiwan/shanghai.
I flew to Okinawa from Osaka and it took around 1 hour. I went with Skymark airline, it was the cheapest. Think of it as Jetstar of ANA.
SKYMARK
One good things for aussies is that the place is the most Americanised of all of Japan thanks to the American base there. That's a big downside too in my opinion. But at least the language is not a problem. The main Okinawa island is quiet big and I hired a car for few days, went to one of the biggest aquariums in the world (2 hour drive from airport), they had 3 whale sharks there. It was pretty good and entrance was quiet cheap, around $18 for adult I think (terrible memory).
There are lots of beaches everywhere, I read bunch of reviews and used google maps satellite photos. Issue with the main island is, the best beaches are taken by the US army base and it causes a lot of issues with the locals.
After that I caught a JAL flight to small island even further south (about 40min flight) to Miyakojima. It's a great little island and I've stayed there for 4 days. Great for snorkelling and what it considered one of the best beaches in Japan.
I wish I had 1 more weeks time, I wanted to explore Irimote island, which is one of the largest covered Jungle islands and Ishigaki island. + lots more islands. Something to suit everyone's tastes. Best time to travel is August, but it will get busy. Other months are less busy, but you will get higher chance of typhoons.
I'm already planning a long trip next year
