The words of the author, not mine (I haven't looked at it yet). HellKnightX posted a tutorial for Doom3Edit (the built in Doom 3 map editor) on moddb.com. Head there to get it.
The description reads:
The Ultimate DOOMEdit Tutorial since doom3world.org is down made by me. You NEED DOOM 3 Resurrection of Evil to run the map because there are certain entities that only work in resurrection of evil. I used all of the editing entities such as func,target,trigger,path. Some of them don't work. I want to help people with this tutorial aimed map. Please read the read me file. Thanks to: ID Software EMO Level Designer doom3world.org If you have any problem send message to me. Thanks-Kılıçarslan