There are certainly lots of ghost towns here in Montana ... old mining camps up in the mountains, and homestead villages out in the prairies. I'm a particular fan of the prairie ghosts, partly because they don't get as much attention, and partly because their settings can be exceptionally evocative. And for me, the old towns don't even need buildings in order to be interesting.
Here's a photo I took when I visited the site of Coburg, Montana a couple of years ago. All that's really left is a few feet of concrete sidewalk, marking the long-vanished site of a building that once housed the general store and post office. And up on the hill, a little ways away, there's an old building foundation ... maybe it was where the schoolhouse used to stand. And that's it.