Plain coconut water is literally just the water on the inside of a coconut. So if you can get coconuts at your grocery store you can get coconut water. I also found this recipe on how to extract and flavor the water: http://www.eatnapplay.net/2013/03/04/make-your-own-coconut-water/.
About Celebrity Solstice. Celebrity Solstice is a large ship, carrying 2850 passengers and 1246 crew, and sails from Sydney, Australia and Auckland, New Zealand.
Like most cruise ships, the Celebrity Infinity lounges have drinks of the day specials that match the day of the week, and Cellar Masters has wine tastings.