Like you said in the original post. They are all directly above the equator. Each satelitte has its own orbital slot. Satellites visibli in North America will be the ones from approximatelly from 50 degrees W to 150 degrees west. Satellites are "stationary" in the sense that they are always in the same location in the sky.
Whn we talk about communication satellites, we talk about satellite in geastationary orbit and "clarke belt". It is about 22,2240 miles up in the sky and everythink there moves in the same direction and in the same period as earth. Because of that they always are at the same location in the sky.
Maybe you can see them sometimes but they are very small. They won't apear to be moving to you. If you set your dish to point to 97W (Intelsat Americas 5), that's all that is to it. 97W will always be at 97W an you want have to move your dish or anything else just to eep up with the satellite since it is always at the same location. You only use your motor if you want to move to a different satellite.
Motors like
Sadoun sells track the clarke belt in the sense that once you have it set up, it will be able to move to any satellite along the arc (clarke belt looks like an arc).
Linear Mode
