First contact the seller and ask for a refund. He may require you to return the item. If he does, use a service which is Delivery Confirmed.
Some sellers will accept photos of a broken or damaged item instead of a return, but they are not required to refund unless you can prove return Delivery. Not shipping, delivery.
If you have been unsuccessful with the seller, here is the Resolution Centre.
http://resolutioncenter.ebay.ca/
