are the names different regionally or is there a difference in ingredients?
As you mention it depends on where you live. I'm not sure now but I believe sugarpaste, flower paste, and fondant are all basically the same (slight differences). Gumpaste is similar - fondant but has certain gums added so it stretches (allowing one to roll it very, very thin) and hardens much quicker.
Sugarpaste, rolled fondant and plastic icing are the same thing but the names differ regionally. Flower paste and gumpaste are the similar to each other, from the recipes I've seen. You wouldn't cover a cake in gumpaste because it would dry rock hard and not be tasty, but rolled fondant (aka sugarpaste) is used to cover cakes all the time.
What she said!