A friend of mine has a music blog (not sure what s/w she's using). In this posting, she has an embedded/streaming music player. (Not just a link, but a player with Play and Pause buttons.)
The default recommendation is to use a SWF player called DewPlayer. However, you can easily configure other players such as QuickTime or Windows Media Player depending on what you want to stream the music.
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You could probably try this plugin:
http://forums.b2evolution.net/viewtopic.php?t=7825
The default recommendation is to use a SWF player called DewPlayer. However, you can easily configure other players such as QuickTime or Windows Media Player depending on what you want to stream the music.