XNA is not a drag-and-drop game maker system. It is a framework for writing games. You have to write the programs yourself.
Making maps for games is a very broad topic. It depends on what kind of maps you're talking about.
At any rate, it sounds like you're looking for something that XNA is not.
However, you're not going to find those kinds of programs here. These forums are more dedicated to developing game with Microsoft Technologies and not with map creation programs for specific games.
If you are really interested in making maps for your favorites games, then I would recommend you find some forums specific to that game and start asking how to get started making maps for that specific game. That's probably your best chance for finding the answer you want.
Hope that helps get you pointed in the right direction.
Check out http://www.gamemaker.nl/ for a game making tool with built in editors.
Otherwise waht george said is right, unless the game has a modding editor provided for you then the game designers likely used a combination of a 3d editing tool (maya, 3ds max) and photoshop.