Yeah, just make your music in MP3 or WAV format, then put in
Steam/steamapps/username/gameyouwantmusicin/sounds/music
Please note the you may need to create the last two folders. Also note that if it is in MP3 format, you won't be able to preview it in Hammer but you will hear it ingame.
So others can hear your music in the final map, use
PackBSP.