I put fondant on a practice cake and a couple of days later the fondant looked greasey. Is that normal? Is there a way to prevent that?

Did you roll it out on a greased board or on a powdered sugar board? Did you refrigerate it after covering or let it sit out? Did you brush it with water or any other liquid to get the powdered sugar residue off? A greased board will leave a sheen of the crisco on the surface of the fondant. If you refridgerated it what you could be seeing is condensation and that will dry out if you leave it at room temp. Lastly if you brush the cake with anything liquid you will leave a sheen on the fondant.

If you did none of these then I would suspect that maybe your fondant didn't have enough powdered sugar to begin with.

Just some ideas...

Cat