Question: Large Wall Map of the U.S. with County Outlines?

Shonin writes:

I was wondering if anyone would know where to get a fairly large wall map of the U.S. that only showed county outlines? I used to have one a long time ago, but I have not been able to find anything since even though I’ve gone to all the expected places, like the USGS sites, and the on-line map stores. It doesn’t seem like it should be such an exotic thing, but it is impossible to find. I should point out that I want to buy a paper copy, nothing web-based. If anyone has any suggestions I would be very appreciative.

So, any ideas where such a map could be found?