I have a tub of black Duff's fondant I bought and opened last year. It smells, tastes and looks fine, but there is no expiration date so I'm wondering if it is still ok to use. I've used it a few times throughout the year and kept it in my cupboard wrapped in plastic and inside the tub.

As long as it's wrapped well, it can last for months. If you're in doubt about how soon you'll be using it again after it's opened, you can freeze it for months on end (well wrapped, of course).

I have a question too...can it be wrapped in plastic wrap and then wrapped in foil? It's hard to buy fondant or gumpaste because I don't make cakes for a living...only for special occasions (at least right now)...but I would like to keep some of the supplies around...

Yes, Sweet_Cakes, you can do that, too. I usually wrap it in two layers of plastic and a zip-top bag.

What about gumpaste? How do you keep that from drying out? Is it the same way?

I generally treat gumpaste and fondant the same way.