YouTube
YouTube needs no introduction any more. In contrast to some years ago, I can find all stuff for my music history and music theory lessons!
www.youtube.com: click here
However if you need more, have a look at the following music streaming services.
Spotify
Think of Spotify as your new music collection. Your library. Only this time your collection is vast: 10 million tracks and counting. You can create as many playlists as you like from this collection - just drag and drop the tracks you want. You’re free to share everything you listen to on Spotify with your friends - tracks, playlists, the lot.The open version is free!
Spotify is currently available in Sweden, Norway, Finland, the UK, France, Spain and the Netherlands.
www.spotify.com: click here
Grooveshark
Grooveshark is an internationally available online music search engine, music streaming service and music recommendation web software application, allowing users to search for, stream, and upload music free of charge that can be played immediately or added to a playlist. http://www.grooveshark.im: click here
Naxos
The website www.naxosmusiclibrary.com has complete catalogues or selected recordings of over 250 independent labels. Online listening is possible: use the button FREE PREVIEW (below). www.naxosmusiclibrary.com: click here