I've tried to find the best too!
I read all about food on this forum, and then made a trip to the store. I have not been able to find Canidae or any of the others that Boxer_Mom has listed. (Wellness, Innova, California Natural, Solid Gold, Eagle Pack Holistic, Flint River, Chicken Soup, etc).
We compared Science Diet, Eukanuba, Nutro, and a few others that were really bad (Beneful, Iams - did you know Eukanuba is Iams?). Science Diet and Eukanuba were full of corn meal, corn gluten meal, by-products - not what I'd want to feed my doggie! Beneful was probably the worst that I checked out. The best out of these that I found was Nutro Natural Choice Lamb & Rice. It was the only one that did not contain by-products or some type of corn.
Comparing the brands' ingredients is the best way I've found to find the food you want. The most expensive isn't always the best. I would like to move to a more natural diet as time progesses. I hope you find one that is right for you! Good luck!
Erin