About 6 months ago, I was introduced to
Royal Canin. It's made in breed-specific blends to support the nutritional needs of a particular breed's metabolism, phsiology, digestive peculiarities, allergic predispositions, etc. My dogs love it and from all appearances it works as advertised. Even my Katrina refugee who had all sorts of infections, infestations, and appetite/digestive issues was kicking out firm stools and eating regularly within a few days of starting on it. The corporation is French, so I feel like a little bit of a whore for buying it, but what you buy here is made by their US division at their US facility. It's a little more expensive than a lot of other premium dog foods, but nothing's too good for my family.
I have had good luck feeding a Chicken and Rice food that is packaged here for a local Farm supply. It's equivalent to the other premium foods such as Eukanuba.
It's not corn based, which to me is one sign of a quality feed. Corn is a filler, and in my experience, there isn't a digestive system in the world that can actually digest it. So - all the corn just ends up going out the dog remarkably unchanged from how it went in.
The other thing I look for in a feed is that it contains no unidentified "animal" as the meat source, as that almost always indicates horse meat (among other things at the rendering plant) and I refuse to support that.