GNSmud

Curiosity's SD3 site contains a lot of useful information, such as maps, directions, and item stats, for players. It comes with two caveats - 1) It's based on Shadowdale MUD, which is the base Mud for GNSMud, and 2) It's about 15 yrs out of date. Even so, most of it's info, especially zone dirs and maps, are still relevant.

You can find it at:

http://www.curiosity-shoppe.com/sd/index.shtml