I sent the site owner a message asking about the sizes for the different puppets. He is "OobiDad" on eBay. He was nice enough to give me a rundown of each one.
Premium Eyes: Fit hands from 3 year olds' to even the largest adult hands by squeezing the band with your fingers to adjust, they are the most adjustable of all the Eyes.
Creature Eyes: Fit hands from 3 year olds(normally) to most adult hands(by pulling the eyes apart to adjust, the plastic is a very nice quality flexible plastic).
Novelty Eyes: This is a rigid "cheapy" plastic, it cannot be adjusted and must remain in it's manufactured size, fitting a 3 year old's hand to maybe a 7 year old's.
Googly Eyes: These are the same type of plastic used for the Creature Eyes so they're very nice quality and flexible but are manufactured to fit only children's hands up to maybe 6 or 7.
So now you know. I'll be getting a couple of the premium ones and a few wigs. I'll have to judge the quality for myself before giving them away as gifts.