Diamond has really made it tough on folks wanting to change. They make a lot of foods that I would've happily recommended a month ago...but not right now. (Canidae, Solid Gold, CS, etc).
Fromm Gold runs about $25 or so for the 15 lb bag. (I usually buy 30 lbs and it was around $45 for the Gold--but I used to use the 4 Star line which was more like $53).
Then you always have something like Eukanuba or Pro Plan. I know a lot don't like them, but I'm not opposed to them and have good results with the Eukanuba. (Better in fact, than some of the higher end foods). I just paid $37.99 for 40 lbs (on sale) before taxes--but that is the big bag.
I have heard good things about Nutrisource, but have not personally used it and cannot get it in my city--so didn't investigate further. Oh and Precise, I think it is...but do not know the cost on it.