no power after generic charger used

Have you tried other adapters? Will it still sync to the computer with the usb cable (if it is dead, you can still try to let it trickle charge from your computer). If no adapters work then check the bottom port for any obvious signs of damage. I usually charge customers roughly $80-$100 to replace the 30 pin dock connector. If it isn't the dock connector then something is probably wrong with the logic board and the price will be fairly high.