Here's a cheap source for small beacon lights: http://www.orientaltrading.com/ui/br...d+Beacon+Light
It doesn't look like the quality is very good but they are cheap and that can be very important late in the game.
Where are you at in California?
depending on the power/type of fog machine you are using, a decontaminate scene would be awesome. Most people love the use of fog. You could easily put together a custom MP3 and have it say something like "I got zombie juice all over me, get it off, get it off" and pssssssssssssssssh the blast of fog acts as the decontaminate. I have seen this type of thing done a few times and when done right it can be really cool. The above is just a quick example...hopefully you get the idea.
www.noxarcana.com great zombie music, check out there zombie influx cd good sound bites of a zombie apocalypse!!!