How to identify and report a scam online store?

Dont count on PayPal. We are going through the same scam and PayPal is taking the scammers side. Told us that " they (the seller) entered the same tracking number on their account that they used on our invoice and it says shipped." Are you kidding me? How the eff does that prove its shipped or that there was even a item to begin with. What a joke. Obviously they didn’t check the tracking number because if they had they’d know it was a fake shipping service and there is no shipment with that tracking number! Also they didnt bother to go to the actual store on our invoice because if they had , they’d know it doesnt exist! PayPal will not help us!