Audacity Ogg - How to Convert Ogg to MP3 in Audacity and Vice Versa?
Audacity tutorial: Converting to mp3 or AAC and other formats, example: Matthew Smith - epic orchestral synth music for film and game effects; Buanzo's LAME mp3 library
Audacity on Mac - Export to mp3 - Media@UP
Extract audio from video using Audacity – Software RT
How to Export an Audacity File As an MP3 in 2 Simple Ways