surfing
Surfing is popular in Okinawa, but it's not particularly easy: waves break over very shallow shelves of reef and/or basaltic rock, resulting in challenging waves. Surfing spots can be found all over the archipelago, but most surfers surf off the main island. Check out Mensore Surfing for weather forecasts and up-to-date info.
watersports
Okinawa is the best place in Japan for all sorts of watersports.
fishing
Okinawa has some of the best offshore fishing in the world. Some fish are seasonal, but there are fish for every season of the year. Marlin, mahi mahi, and various species of tuna are some of the fish that are teeming in Okinawa's crystal clear seas. There are many places where you can find a boat to go fishing, but as with diving, language can be a major issue. Some charter services provide fishing tackle, and others require you to rent fishing gear. The 2008-2009 Issue of "Okinawa Island Guide" has featured Saltwater Fishing Okinawa for catering to Japanese, English, and Chinese speaking travelers.
The cost for offshore fishing in Okinawa is comparable to other charter services around the world. Usually about $100 US Dollars per person for walk on charters, and up to $1,500 US Dollars for private charters.