Have you already opened Dispute through eBay?
If you have not, do it immediately.
The first suggestion is to contact the seller, but since that is not possible escalate to a Claim.
If you have not opened a Dispute with eBay and it is now too late (you only have 30 days after the last predicted date of delivery) go instead to Paypal.
The PP Resolution Centre is hidded under Tools at the top of your account page.
The first suggestion is to contact the seller, but since that is not possible escalate to a Claim.
Tell PP that your sellers is Not A Registered User (NARU) which will speed things up.