Here's a tutorial on terrain editing for the 633 build of the Unreal engine and editor. This version is only available to the Unreal Engine licensees however I believe most mappers find it interesting:
http://www.epicgames.com/UnrealEngine/Build633Tutorial.html
Make also sure to check out the engine news as well as these cool screenshots which show the new limits for polycount (max polycount is now 150-200x higher than for UT):
http://www.epicgames.com/UnrealEngineNews.html
And the images:
http://www.epicgames.com/unrealengine/xbdemo1.jpg
http://www.epicgames.com/unrealengine/xbdemo2.jpg
http://www.epicgames.com/UnrealEngine/Build633Tutorial.html
Make also sure to check out the engine news as well as these cool screenshots which show the new limits for polycount (max polycount is now 150-200x higher than for UT):
http://www.epicgames.com/UnrealEngineNews.html
And the images:
http://www.epicgames.com/unrealengine/xbdemo1.jpg
http://www.epicgames.com/unrealengine/xbdemo2.jpg