Electric motors are very standardized (I'm assuming its the motor that died, not the fan blade) so I recommend you look for an electric motor shop which could either rebuild or replace the motor for you. Try the yellow pages or do a google search. For example, some years ago I pulled a small motor out of a computer printer and took it to a nearby repair shop. Within 24 hours I had it back and was re-installing it in the printer. It wasn't my job to maintain this equipment, but since I needed the printer to perform my work this was quicker (and much cheaper) than going through the manufacturer's field sevice.