Looking for that perfect soundtrack for your homemade haunted house? Tired of those cheesy Halloween mix CDs? Need some spooky music for your Halloween party? San Diego-based Slacker has the solution for Halloween enthusiasts: stream those sounds from its streaming audio service. Slacker told its users Monday that it has added a number of Halloween-themed stations which users can find and use to complement the season. The audio service said the channels include everything from sound effects, to classic horror film scores, to kids music, and even Halloween Heavy Metal.