I have an American Tourister one. It probably came from Wal-mart, Target, or JCPenney. I remember it was in the luggage section, because I picked up some luggage tags at the same time.
Haven't used it very much other than some touch ups on the formal nights though. I give my dress shirts to the Steward to get pressed. My casual clothes seem to self un-wrinkle from the humidity, or I just don't notice. Good luck, and just make sure it is allowed to be brought onboard as Lisa noted about the policy on Celebrity.