Let's say your Real Audio (or MP3) file is called "file.rm" (or "file.mp3") , and its URL is http://www.yourdomain.com/audio/file.rm (or http://www.yourdomain.com/audio/file.mp3) and you want that to stream off your site.
What you would need to do is create a text file called "file.ram" (or "file.m3u") and make the contents "http://www.yourdomain.com/audio/file.rm" (or "http://www.yourdomain.com/audio/file.mp3") and save it. Then, link to THAT instead of the file.rm (or "file.mp3"). What happens is RA Player (or MP3 Player) sees the downloaded m3u or .ram file, opens it, sees the URL, and starts streaming.
So your HTML would look like this:
a href="http://www.yourdomain.com/audio/file.ram
More information can be found offsite at www.real.com
