UT2004 links

My favourite portals:

Beyond Unreal with incredible file works archive, Insite reviews (with me involved), lot of maps on Nalicity, and of course their forums (BuF)
Mapraider – very nice map-related portal
Planet Unreal/UT2004 – another complex UT2004 portal
Unreal North – guide to the Nordic UT2004 community
Ultimate Community Map Pack – no need to introduce :-)

Mapping, tutorials:

Hourences Help Site – Hourences consolidated all his tutorial stuff into shape of this amazing site. There are also two example chapters from his book about general level design (The hows and whys of Level Design) and some fresh new tutorials. I simply love this guy. ;-)
Angel Mapper's page – also nice tutorials – even for beginners. Nice one about optimization.
Hazel's homepage – another tutoarials and nice skyboxes! :-)
Sjosz Level Design contains some tutorials too
UT2003/2004 Advanced Bot Pathing Tutorial – by Blitz.
Unreal Tournament 3 Level Design – Wiki I started about UT3 Editor and level design principles

Video Training on 3D Buzz – tremendous load of tutorial movies about Unreal Technology, Maya and many more. You need to register first – but it's worth because hours and hours of content are for free.
UnrealEd on Wikipedia – check the bottom of the page for links too.
FAQ + a lot of links to anything you can think of :-)

Some other sites:

Taleweaver's UT2k4 Guide – my first favourite guide to the UT2004; I made it to the ONS team with this guy meanwhile ;-)