Invincible Overlord wrote in Down in the Dungeon [Squadron/Signal Publications inc.]:I snagged this link because it was easy to find a picture of...
GROGNARDIA: Down in the Dungeon
What's it worth, and should I bring it to Gencon to sell to a fellow Acaeum member?  

I like that write up. Very well done.

As for value, I guess it depends on who you show it to.
I have 2 copies of this book and I saw one listed on e-Bay the other day while patrolling for fun finds, but do not recall the price it was set for.
I actually thought about buying that one too; mainly as both of my two copies have binding issues and that copy looked pretty well put together.
I think the binding is a common issue for this book actually.

As for value?
I listed one of my copies on e-Bay at just under $20 and it never sold, though that was a while ago.
Even though it is pretty uncommon, IMO this item is seriously under valued by the collecting community as a whole.
Seems this is a specialty item that one has to look through at leisure to truly appreciate the beauty of the book as a whole.

Gnat the Beggar wrote in Down in the Dungeon [Squadron/Signal Publications inc.]:Seems this is a specialty item that one has to look through at leisure to truly appreciate the beauty of the book as a whole.

It's a great book; I found a copy for less than I expected (<$20). As you've stated, it probably slips under the radar because people don't realize what it is, an art book rather than text with a few illustrations.