you can't take out vocals, cause it would leave a hole in the frequency response and it would sound shitty. any 'plugin' for editing like that will just drop certain frequencies that voices are typically in, which will also take out any other instrument that's in that range. if it fills in that hole, it will fill it with something called dither, which is light noise used to match the frequencies in the missing range and increase bit rate when trying to improve quality. leaving you with bad quality. best bet is to take the song, get some kind of program (protools) where you can automate the gain on certain frequencies, then you can go through and do it manually.
i have to edit some songs for my radioshow and instead of removing words i just reverse them. if that's the case.