How long has it been since you paid for your item? And where is it coming from?
Your first step is to contact your seller directly. Give them two business days (max) to respond and if the seller is from overseas DO NOT allow them to send you another. It will land in the same boat as the first.
Has it been 29 days since you bought it? Wait for nothing, go to the ebay Resolution Centre and open an Item Not Received Case.
Has it been 179 days since you bought it? Go to Paypal's Resolution Centre and open an Item Not Received Case.
Remember, if the seller is from overseas DO NOT allow them to send you another. Even if the seller gives you a tracking number, you've no guarantee it's for YOUR item. It may be a stall tactic designed to make you wait past the point you can complain about it.
If it's been more than 180 days, you are sunk. Try the credit card you used to back your paypal account purchase and see if that might help you.
Best of luck.
