I once used a mod to find out which mod a certain element belonged to when I had to fix a broken savegame, but that was a few years ago.
Now I have the same problem, I need to know which mod contains the element QS_cloth_bazrasring and which one modify the ancestral ghosts (since they frequently cause crashes) and I believe that I used a tool, which could search through all the mods belonging to a savegame, but I have forgot which tool, so what was the name of the tool? Can anybody help me?

http://www.wingrep.com/ is an excellent tool. http://planetelderscrolls.gamespy.com/View.php?view=utilities.detail&id=24 may also work.

What I do, if I have a problematic object is to use a grep tool (currently I use Textcrawler, but there's also InfoRapid Search & Replace or Wingrep. The latter is nagware though, the other two freeware).

I put the object's name in the text to search box, restrict the search to the Data Files folder (not including subfolders) and use a file mask of *.es? to only search plugins and masters. You don't really need to do all that, it just runs quicker.

So, that would identify which mod a particular object comes from.

[Edit: Yeah. What she said]