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Some good foods you can find at Petsmart or Petco are Natural Balance and Solid Gold. There are both okay but I wouldn't pick them.
If you have a privately owned pet store or Pet Supplies Plus you may be able to get Innova or Canidae which are highly recommended by lots of people. These all have grains. If you want to go with grainless, you could get Innova Evo.
My Yorkie gets homecooked meals.