This is by no means a complete listing of where to find early music online, but aims to be a starting point. Additional links will continually be added as resources are identified.
Harmonia harmonia.indiana.edu Current and archived programs.
Millennium of Music www.millenniumofmusic.com
Sunday Baroque www.sundaybaroque.org
A Treasury of Early Music www.live365.com/stations/machali Medieval, Renaissance and (occasionally) early Baroque music.
Allegro! jrabold.net/radio/ Musical Public Radio Programs via streaming audio.
Magnatune www.magnatune.com Many early music ensembles listed.
BBC's Early Music Show www.bbc.co.uk/radio3/earlymusicshow/
Early Music Network Radio www.live365.com Streaming audio with Live360 player.
Performance Today Live streaming here.
Naxos Radio www.naxosradio.com Search for early music.
iTunes www.itunes.com Search for Early Music.
Classical Webcast www.classicalwebcast.com Classical radio stations on the web.
Arkiv Music www.archivmusic.com Online classical music store.
CD Baby www.cdbaby.com Online store for all musical genres including classical.
Ancient Voices www.kmfa.org Broadcast from KMFA in Austin, TX
Monteverdi.tv. Worlds of Classical Music.