The Spa at the GCH is owned and operated by Mandara Spas. They are famous for their spas in Las Vegas, as well as at the Swan/Dolphin in WDW.
I have had Mandara treatments a couple times and they are very good at what they do. They are a bit on the pricier side, but very nice.
They don't really like you to photo in spa areas, due to privacy reasons (that in people in bathrobes and less), but here is a link to their website....
We went last October and we all had manicures and pedicures. It was pricey...But well worth it. We treated my aunt and she loved it I am going back again when we go in December....Its a vacation so why not