Mac OSX MIDI Developers Resource
Caters to developers of MIDI applications under Mac OSX. Online Apple documentation available as well as custom examples.
MacMusic : Audio and Midi on Macintosh
Making music with a Macintosh: Resources, more than 1200 searchable links, downloads, updates, drivers, classified ads, mailing-list, articles, info. All you need to make music with your Macintosh, free and available in English and French.
MacRocks
A comprehensive source for information about making music on Macintosh computers. Features Mac audio news, hardware and software reviews.