Is Metro Graphic Arts still around?
You may recall that they published black-and-white street maps of many American cities, especially in the Midwest. They made wall maps, and they made their "graphic street guides" that contained these maps "in convenient book form." These maps were a legend in the 1970s and 1980s when I was growing up.
But now you look for information about this publisher, and it's like they never even existed. They were still around a few years ago, but now it's like they've been flushed down the memory hole.