This has been mentioned before, as it's one of the areas I haven't worked much on. If you are good at drawing maps I am happy to take submissions.
EDIT: here's a crazy idea. Since the maps are all grid-based, making an "ASCII map" could work too. I mean something like this:
XXXXXX
X....X
XXXX.X
XXXX.X
XXXX.X
Where the X's are the walls and the dots are the floor you can walk on. I can then convert that easily into a better graphical image for example like http://pokemondb.net/maps/abyssal-ruins