In a third-hand account of spa-going, I offer you the results from this year's list of best spas, based on a reader poll done by Conde Nast. I tried going directly to the Conde Nast site, but they offered their results with that annoying web trick of forcing you to click here, there and everywhere to see all the results.
Instead, you can go to A Luxury Travel Blog and see all on one page, the top spas in the U.S., Canada, Hawaii (yes, I understand that Hawaii is part of the U.S., but I didn't make up the categories), cruise ship spas, spas in Mexico and Central America, spas in the Atlantic and Caribbean and top hotel spas.
Take the recommendations with a grain of salt...or with a sugar scrub. Theses spas are not being reviewed by us skilled and trained professional journalists, you know, those of us who majored in spa going and can write about it objectively.
But the list of top spas at least gives you some names of places to research if a solo spa vacation is in your cards. While you're researching, of course, investigate what the solo scene is to see if you'd enjoy going alone.