Ebay seller dispute, help?

I purchased an item on ebay and it was dented and scratched up. I told the seller and he offered a refund at my shipping expense. I aske if he could help with the shipping fees and he refused. After trying to resolve the problem he wouldn't budge so I told him it's only fair to leave negative feedback for the next buyers to know, so I left negative feedback.

I received an from ebay saying tht the seller reported me for "feedback extortion" and to view their policy. After reading I realized I didn't violate any rules. There was no info to follow up or anything.

Does anyone know where or how I can contact ebay about this, because ebay foesn't provide their contact info anywhere.