Unfortunately, it appears that there aren't any reasonably useful grid square maps floating around the net, at least not that I could find. Having printed out maps is very useful during contesting, for locating other stations.
I resurrected Brian Reid's netmap program (unfortunately not publically redistributable) and modified it to produce Maidenhead-style grid square maps. These are the ones I hacked up in a hurry, perhaps you'll find them useful:
For those strange non-postscript people, I did a pdf of one of them, and could do others on request:
I can also generate maps for arbitrary longitudes and latitudes, though I don't necessarily have useful political data for all of them. One project might be figuring out wtf to do with SDTS mapping data from the USGS web site, but that's too much effort at this point. Instead I should be debugging emacs.
There's also a short todo list.