Well, there's one thing you can get early in the game, which does work very well against undead - Azuredge, throwing axe. Oh boy, I have had much fun with it. It's just too funny to walk to some lich, hear their "cryptic" speech, where they promise a house of pain and what not else, then the fight starts, my char just swings his arm once and... BLAM! Dead sucker, who's triggers and whatever else are still going off
Of course, it's not a key to "everlasting dominion over undeads", as they still can roll against it - albeit with a penalty - and get away. From that one hit, that is, next time wont be as lucky. But, pack it with you and let it fly at times, it can make things much easier.