Hello Kreegle, hope this helps you.
I had this problem too, and as far as i can see the best thing is to use things like axes and hammers on the stone caves (I think there may actually be one of these in the caves, but don't quote me). It helps if you have some followers with missile capabilities as the other hand to hand ones seem to just get mashed.
A word of warning - swords break damn easy on these guys, and don't wear any aromour you value highly as they damage that too. Generally this is true of the axe/hammer you use to kill them too, as it will be a bit wrecked by the time you escape, blinking into the sunlight.
I hate this bit - it's too damn hard and it doesn't fit well with the majority of the rest of the game.
EDIT - Grrrr... Beaten to it!
![icon_mrhappy :D](./images/smilies/icon_mrhappy.gif)