i finally was able to get a relay from some autoparts store, but it comes with absolutely *no* documentation. like zero. ziltch. it doesnt even (haha. I'm not even 100% sure its a relay, but the drawing on it suggests it.) Anyway, I am just assuming it requires 12 volts.
The "standard" automotive relay is known as a "Bosch" relay (it's a brand name, but has become something like "Kleenex"); most are SPDT or SPST in function, and have a standard pinout. There are sockets available for them, too. However, most of the time you can't go into an auto parts store and just ask for a "Bosch" relay; they'll look at you funny, then ask for a make, model and year of your car.
Here's a couple of sites detailing them (in looking this up, I found out that they are now made by "Tyco" - but they'll likely be referred to as "Bosch" relays for the rest of time):http://www.classictruckshop.com/clubs/earlyburbs/projects/bosch/relay.htmhttp://www.bcae1.com/relays.htm
They aren't too expensive new, but if you have "pick-ur-part" auto junkyards, they may be found there even cheaper. They are fairly easy to control with small transistors and the like.
Also, another source for smaller relays are old modems (internal or external); they will usually have one for taking the phone line off-hook.