Sending a return label for refunded product

[triplessales]

I may have gotten the process backwards but I refunded the price of an item I sold that did not work. I need to have the item sent back to me but I cannot figure out how to send the buyer a return postage label.  I thougth I could do ith through eBay but something I read said do it through paypal. I owuld like to buy the postage and email it to him so he can get it in the mail asap. Any help is appreciated.