mrfox, more than likely you're right about your calipers, but if the boot isn't torn you might want to check your brake hose, even if it looks fine. It's made of 3 different layers of rubber and if the inner layer implodes on itself you can't tell. What happends is when you apply your brakes the fluid pushes past the imploded part but then gets stuck and holds the brakes on.
If you buy napa's united pads they'll come with the shims (and have the slots in the pads and the shamfered edges) I think they're like 40-51 for the front set, rear is a few dollars cheaper. They'll prob try to sell you the cermix pads (it's whats shown as OE replacement in the computer), which are like 99 dollars, but the regular AE pades will be fine. Some stores also carry the metal axxis brake pads (performance) (which I have, I love them

) they are like 38 or so dollars.