If you believe that your item has not arrived after a reasonable amount of time, the first step we recommend is to check if the Seller has provided Shipping and/or Tracking Information, and/or contact the Seller: How do I know if my order has shipped?
If the Seller does not respond within a reasonable amount of time, or you're unable to resolve the matter with the Seller, please file a claim with PayPal, as your eligible purchase + shipping cost will be covered by PayPal's Buyer Protection. This is a quick and fully automated process, which can be initiated from the bottom of the transaction details page on PayPal, by clicking on the "Need help? Go to the Resolution Center for help with this transaction..." link.
Note that as all payments are handled directly through PayPal between the buyer and seller, we are not able to initiate refunds ourselves. However, by following the above instructions you should be able to receive a prompt refund from PayPal. We also recommend that you leave appropriate feedback once the matter has been resolved.