Heres my way:
First import the sound into your library (duh)
Now right-click on it, select Linkage, check the Export for AS2/AS3 option and type in your Linkage Name
Go back to your stage, select a frame and right-click for Actions
Type in this code:
var btnsound = new Sound();
Now, if you want to play this sound when the user rolls over a button do this:
This is play the sound once. If you want to loop the sound, just change the 1 into how many times you want looped. Obviously, you can change the rollOver option for almost anything. Hope this helps
PS: Flashkit.com or Sounddogs have really good sound banks.
Don't you ever, ever, EVER call me a Noob. I mean it!