I don't use IE anymore. But some software is written as a BHO or Browser Helper Object. You can try WinPatrol as it has a separate category to show all BHOs. You can delete them right from WinPatrol.
WinPatrol has both free and paid versions. But the BHO stuff is included in the free.
http://www.winpatrol.com/
edit: In WinPatrol the menu is IE Helpers.
Apparently what it does is let you remove the registry entry for the helper without deleting the file itself.