I have purchased a number of magazine subscriptions through ebay sellers.  Most have been slow but relatively trouble free.  Amusingly enough, I usually get confirmation through the magazine itself which asks me to renew my not-yet-received magazine.  However, recently I realized that the gift subscription that I bought for my son-in-law's Christmas gift had not arrived.  When I wrote to the seller, I received no response.  I checked the feedback of the seller and saw 232 NEGATIVE feedback and was ready to kiss that money goodbye. It was too late to try and get a refund from paypal since it was 6 months since the purchase.  However,  I printed out the receipt from paypal using the history feature and contacted the magazine itself.  They took all the information from me about the seller.  A few days later, they contacted me that the subscription would be honored and they had collected the money.  This is obviously a last resort option but many of these magazines are basically giving away the subscription to get addition subscribes for their advertising fees and also they want to try and sell further subscriptions.  So if you have paid for a subscription and not received it, you might as well try to get the magazine to honor it using your paypal information, a cashed check or any other proof that you might have. 

Ebay recently stopped allowing magazine subscriptions to be sold since they take at least 2 months to receive.  This meant that many buyers who had already purchased magazine subscriptions found their sellers gone and no longer responsive to feedback or ebay reporting.  This doesn't mean that you don't still have an option of dealing with the magazine itself to see if you can still get the subscription that you paid for.   Sometimes positive action is better than sitting and waiting.