I also have a large collection of sounds you may download. Just try the following link:
http://rewindshow.com/haunt/hsed.asp
It takes a while to open up, but there are a lot of high quality sounds there, including an electric shock sound. You would have to loop it and add screams and other noises, but they are all there for you to play with, as well as a large collection of halloween tunes.
Right click on the link you want and choose the "Save Target As" option.