Joe, get a small flashlight and take a good look at your brakes. In many (most?) cases we can see the pad material and see how much thickness is remaining. If you have more than 1/8" of pad material remaining, you're OK, but if they're close to 1/8", you're getting close to time for new pads. You can look at the contact surface of the rotor, feel it with a finger, and see how grooved it has become.
Look at the rears. If you see a shiny disc (a.k.a. rotor) like the fronts, you know you have rear discs. If you have a big rusty ugly iron circle, you know your have drums. If rear discs, you can probably also see the remaining pad thickness.
I really like my results with Performance Friction's Carbon Metallic pads on my truck. Well worth hunting for.