Ok.. i Have a couple of questions. What sound should an alternator make when ideling with a mechanics stethiscope. And i was also told that i could take off my supercharger belt, and start my car, to see if it was anything ont hat belt that was causing my problems. Is this true. If i just start it for oh 20 secs. thanks.

A working alt will still make some noise but it will sound like a quite hum. If the alt is going the pitch usually gets higher and a lot louder.

Oh, and if the bearings are going you can usually hear an uneven rattleing sound as well.

Would the bearings shake the car some on idle?

Not from the alt. If the bearings were all shot ( to the point of seeing it smokeing while trying to turn) it still wouldn't shake the car. Yes, You may feel a slight vibration from it thru stuff, but nothing strong enough to say move the engine on the engine mounts.

If your alternator is underproducing power, it may be inducing an ignition under-voltage, which could cause a miss, and shake the engine.