please consider carefully. Unless your site is the kind of place where visitors would expect to find music playing you might well find that you'll drive most of them away.
Many people (me included) find web sites which play music very irritating, and they avoid such sites like the plague. Some music files take a while to download as well, and if you add Flash into the equation you'll be slowing down the page loading even further.
Now that I've got that off my chest I'll try to help
click here to find out how to do it.