What is the best way to convert .m4r ringtones to .mp3 format?
Converting iPhone Ringtone Files directly to MP3 Audio Files (.m4r to .mp3 conversion) should be possible and quite straightforward.
Use one of several audio editing programs or (online) conversion tools, such as AVS Audio Converter or Xilisoft iPhone Ringtone Maker, which allow users to import M4R ringtones and export them in MP3 format.