First thing you have to do is figure whether the antenna motor is broken or just the mast. If it the motor, then you'll have to spend some money. However, if its just the mast, you can get one off ebay for about $25.

Most likely, the plastic cable of the mast broke. If this is the case, then all you need to do is remove the plastic lining inside your trunk. Unscrew the antenna motor , open it up and take out the old antenna. Put back the motor, then feed the new antenna cable through the top.

I was going to do a s2k atenna, but I hear reception is bad w/o the factory signal booster. I listen to a lot of AM, so the s2k would be no good to me.