I can tell you where not to go...we had really bad luck with the tea cart near Exp. Everest in Animal Kingdom (don't remember the name...something like Royal Anandapur Tea Company?)
Anyway, they have cap. & other coffee drinks listed, but after our experience, I wouldn't recommend the place. They had a frozen mocha machine which looks like it should deliver a nice slushy-type frozen coffee drink. NOT! The machine looks like it's slushing it up just like an icee machine, but what we actually got was 12 oz. of something with the consistency of watery chocolate milk...and even less flavor...very little coffee flavor. And it didn't seem to have any caffeine "kick" at all, although the CM said it was a coffee beverage.
Yuck - and to top it off, it was not included as a snack on the DDP, so paid cash for it - over $4 with tax. All of the fancy coffee drinks there were in the $4-5 range; plain coffee was available for less though.