Dino the Dark Dragon has made some updates to the Ultima Underworld content on his excellent Ultima page:

If you’re planning to journey through the Stygian Abyss anytime soon, I think you’ll like the new Ultima Underworld 1 Magic page I’ve just added. It’s not just a list of spells. You can pick what runes you have available from the rune bag on the right, and the spells you can cast with those runes will be highlighted.

And having recently played through the game again, he has also been expanding that content considerably:

…the Ultima Underworld 1 Info page is getting a lot of new additions. As if the recently released Magic page wasn’t enough, there is now a Lizardman Language reference and translator, and a new Fun section. A subsection on combining items has been added, and a correction has been made to indicate that there are actually 2 resilient spheres in the game. More information has been collected during the playthrough, and will be added gradually to the site.

Oh, and he’s been making some general updates to the site as well:

I’ve also gone over all the links to the recently departed UltimaInfo.net, and changed them to point to an archived version instead.

The magic selector is an excellent reference, by the way, and also pretty darn fun to play with.