Ogg Drop (OS x 10.1+/os 8.6+)
Ogg drop is a freeware application that will encode aiff (.aif) sound files and audio cd tracks into an ogg vorbis (.ogg) file. ogg vorbis is an alternative to many other encoding formats such as mp3. ogg drop currently works on mac os classic (8.6 or higher) and os x.
http://www.nouturn.com/oggdrop/