I don't know why Creative Assembly decided to call their map editor TEd, but they did and we must live with that. Yesterday on May 23rd they released TEd for free for Total War: Shogun 2 and Fall of the Samurai Expansion. With this tool, which you download from the tools section of Steam (if you own either of those games), you can create your own battlefields for singleplayer or multiplayer, but you cannot use them for the campaign. The most useful thing about this editor, other than the people who just want to create their own maps for fun, is that it should help modders quite a bit. All of the Total War games are notoriously difficult to mod, but even with those difficulties some glorious modifications have been created, like Third Age Total War, and now it should be less tricky to create custom maps for modifications.

This map editor is impressive and they claim it is the same tool the developers use in order to create levels for Shogun 2. They even claim that it is fairly easy to use for those with little experience with modding or map creation. It has pre-existing custom brush sets, particle effects and a whole slew of options, but it also allows you to bring in your custom ones. Currently they are having problems with 32 bit operating systems, but the editor is specifically designed for 64 bit operating systems and there aren't any known problems with that. There is a lot of information on teh editors, which I will link to below, but take a look at this episode of Rally Point and see the editor in action.