Big chain petstores carry basically what brands they think they will be able to sell (aka what ones you see commercials for on tv) or what companies are willing to pay for a deal with Petco/Petsmart to sell their mechandise.
Authority is actually Petsmarts brand food, I believe. If I were you, I would try to go with Natural Balance or Wysong first, the ingredients are REALLY good, and I have fed it before.
Sometimes if you find a smaller local store, they will sell better brands and more brands that you can't find at big chains.
From Petsmart, the only foods I personally would consider feeding:
Nutro Maxx(and Nutro Natural if they have it.)
Pro Plan (You can try this food, but I've heard bad reviews about it, it gave one of my cats a urine problem too.)
Avo-Cat Breeders Choice
These are in no particular order, and some are better then others, but the above listed are all better then things like Purina, Wiska's or Frisky's.