There are a lot of really good foods - although right now some of them such as Taste of the Wild are involved in a recall. You can read more about that here:
http://diamondpetrecall.com/
And here:
http://www.honestdog.com/2012/05/04/diamond-pet-foods-and-the-ever-expanding-rolling-recall/
But there is also Fromm (which I have fed with good results), Blue Buffalo, Nature's Variety, Orijen, Acana, and many others. There's a fairly good site that can help you choose. A lot of people seem to like it:
http://www.dogfoodadvisor.com/
I prefer to give treats and food that are free of corn or unspecified meats among other things. Here's a good list of ingredients that can be avoided:
http://www.dogfoodproject.com/index.php?page=badingredients
That list might seem pretty long... But I've found that the easiest way to find a good dog treat is to look for a treat with ingredients that I can actually pronounce LOL.
Also, some good, cheap training treats can be as simple as some plain cooked up chicken breast, and when I'm short on cash, I get hot dogs and cut them into tiny pieces. I know hot dogs aren't particularly healthy, but sometimes I can't afford anything else, and one hot dog can last me two or three training sessions if cut up tiny enough. Meat is a very good treat for training.