Blog Aggregator listing several blogs http://blogs.botw.org/Business/Arts_and_Entertainment/Music/

And some we read:

DIY Musician http://diymusician.cdbaby.com/

Hypebot http://www.hypebot.com/

Law on the Row http://barryshrum.com/lawontherow/

Music Think Tank http://www.musicthinktank.com/

Sonicbids http://www.sonicbids.com/