This site has streaming audio of many famous speeches. It is really pretty cool.
This site is a resource on the music of composers in the United States, particularly new music. Many full recordings available. Great site.
The Chorus America Convention, held in Minneapolis in June 2012, had a wonderful opening night concert, and this blog creator was there, singing with the Minnesota Chorale. MPR has posted the full concert online.
The Minnesota Orchestra has begun to make their concerts available digitally for very reasonable prices. Cool if you see or hear about a concert and want to listen again.
The Saint Paul Chamber Orchestra has begun to offer full concerts for free online streaming. Really wonderful. Check their “Listening Library”.
This site has full concerts of choirs from all over the world. The International Federation of Choral Musicians has a World Choral Symposium once every three years, each time on a different continent. In 2002, Minneapolis was fortunate to host it. The event was extraordinary, and these concert recordings give a taste of what it was all about.