if you "let itunes manage your music" and the itunes folder is not specified as the same place as your music is currently located it will copy the files to the path specified in preferences.
personally i manage my folders manually and turn that option off and import folders using the "import folder" option.
the only time itunes duplicated anything of mine was when i had unconverted WMA and MP3 for each album.
personally i manage my folders manually and turn that option off and import folders using the "import folder" option.
the only time itunes duplicated anything of mine was when i had unconverted WMA and MP3 for each album.