I want to get an audio file to play automatically when someone visits my site!
Here is the answer,
Most browsers support the EMBED element for this, provided that the user has a suitable plug-in for the sound file. You can reach a slightly wider audience if you use BGSOUND as well. To avoid problems with browsers that support both, place the BGSOUND in a NOEMBED container:
<embed src="your sound file" hidden=true autostart=true> <noembed><bgsound src="your sound file"></noembed>