The installation should obviously have copied ffmpeg to your bin directory (it did on mine). Maybe just purge ffmpeg and see if anything is left in your bin.
Originally Posted by macsmith
Check for ffmpeg, ffmpeg2theora, ffplay, ffserver. I have all of those from installing according to this guide. If you still have them after you run the purge, just delete them and run the guide again (or, to save time, just install the .deb the guide created for you ).
sudo apt-get purge ffmpeg
ls /usr/bin | grep ff