I just bought a 02 A4 quattro with 62,000 miles, coming up tp 70K miles, while im driving after a while, when i accelerate the car shakes, whem i put it on neutral it stops, what could this be? Motor mounts? wheel bearing? alignment? Also i took one of my front tires out and i noticed the rubber cover that is one the wheel bearing it came off could this be causing the noise when turning? or the shaking?

 

Sounds like you might have bad CV joints.
Have a shop take a look at them.
If you have a lot of thick black grease behind your wheels, it's definitely those.