X Lossless Decoder (XLD) is a tool for Mac OS X that is able to decode/convert/play various 'lossless' audio files. The supported audio files can be split into some tracks with cue sheet when decoding. It works on Mac OS X 10.3 and later.
Support various formats
XLD supports the following formats:
(Ogg) FLAC (.flac/.ogg)
Monkey's Audio (.ape)
Wavpack (.wv)
TTA (.tta)
Apple Lossless (.m4a) [10.4 only]
AIFF, WAV, etc
Other formats supported by Libsndfile are also decodable. XLD uses not decoder frontend but library to decode, so no intermediate files are generated. All of the supported formats can be directly split with the cue sheet. XLD also supports so-called 'embedded' or 'internal' cue sheet.
Currently you can choose output format from WAVE,AIFF and Raw PCM. In addition, you can choose Ogg Vorbis (aoTuV), MPEG-4 AAC (QuickTime/CoreAudio), MP3 (LAME), Apple Lossless and FLAC in the GUI version.
THEBATTMAN Seems like a pretty good app. The description claims that it supports m4a (under OS 10.4), but I cannot get it to open such files. These are NOT iTunes purchased, but ripped from my own CD's. (Version 20080503)