i've bought a bunch of different brands trying to be cheap on button downs, all the cheap ones just sit in the closet, never been satisfied for anything I payed less than $90 for.
Best shot in the cheap price range is brook brothers extra slim fit, the sport shirts can be had on sale and I've got plaids for $35-40 that are passable, but I don't really care for the cut/fabric(slimmer than jcrew at least). Still advise springing for wvg (use forum code for 20% off), gitman, toj, etc.
Currently replacing all my junk shirts with wvg.