http://www.petrescue.com/library/find-pet.htm

This website has a lot of good ideas. Keep going back to the shelters. Look in every cage. Don't rely on the shelter employees/volunteers because you're the only one who knows your cat. (How you describe Tricky may not ring a bell with them). Ask if they have any cats in the infirmary. Insist on searching the infirmary. Go through their DOA file. Even look in the dog areas because sometimes (believe it or not) dogs and cats are kept together.