I move my stereo system near the roof windows. I put the speakers outside on the roof (single level home) and play my soundtrack from that - the soundtrack leaves the right speaker to the music, and both Left and right speakers for thunder.
I have a lightning machine hooked up to the left speaker to catch the thunder noise (to give me lightning from strobe and high intensity light).
In my graveyard, I have a cd player on repeat. That CD player has ambiet sounds (whispers, etc...).
In our hidden garden (off the main pathway to the front door) is ANOTHER cd player that has a woman crying every so often.
Under our deck (because it looks like a "caged" area) is another CD player hooked up to LED eyes that come on while the dialog says "Help Me.... get me out of here... I'll give you things you've never DREAMED of having....".
There are other CD players hidden around the yard. They go off with different things every so often. If you stand in on place, you'd swear there were things in our bushes, but because the sounds are faint, you're not too sure you're actually hearing them.
It all works pretty well... until it rains.

Thankfully, I live in California!