Hello Jagat,
Sorry for your bad experience on eBay. 😞
It won't be in the interest of both parties to judge without having reasonable information regarding the transaction. Still, if you feel that a lot of time has passed since you have paid, you can file an Item-not-received dispute with eBay. 😉
You should not think that you are helpless, because sending money through online-payment is not illegal or unaccountable. Since you have the details of your seller's account and the Payment ID of the transaction, you can still produce proof through your Bank's statement. This will be enough to legally penalise a non-performing seller. You can also furnish the seller's name, ID and item details on this forum so that others can be aware of him! ]:)
I hope this will be helpful to you.
Do keep writing!!
BYE :^O