I can't offer the much in the way of a site, except for this one:
The basics are there.
When looking for equipment, stay the hell away from PVC cylinders. You will regret it. Instead, spend the few bucks on a decent cylinder. They really aren't that expensive (the big ones suitable for haunt use are 50 - $100). The quality, durability, and the fact you won't have to worry about them (except for the occasional oil drop or two) cannot be beat. You don't want to be tearing apart a prop in the middle of the show to fix the cylinder, do you?
The valves are a slightly different story. If you can afford it, I suggest going with a real 5-way valve. Again, these run 50-100 depending upon make, model. They come in all sorts of flavors, from 12VDC solenoids to 120VAC and everything inbetween.
Small valves are cheap. If you have a large cylinder and want your prop to move fast, you need a valve that can handle a large airflow. 1/4" is a great size to get.
If you can't afford the real valves, you can hack one. We've used washing machine valves for years. I hate them, but they do the trick. If you need two-way action (yes, yes, shh...), you will need two valves, OR have gravity/spring/bungee do the reset work for you. I hate these valves because you spend a ton on fittings to adapt them to your cylinder, and they are noisy, and are prone to leak.
People have also used lawn sprinkler system valves, and a wide assortment of other things that are intended for air or liquid.
Now, how you control all this mess is an entirely different subject...