From where can I buy a virtual credit card for online shopping?

apply fot the paypal debt card- then only have what you want to spend in the paypal account and put the rest in a regular bank account- I do not think there is a a different kind of card that you can load from paypal- unless you get one from Walmart or somewhere and it has a routing number and account number - some do- then you could enter the routing number etc into paypal as a bank account and do a transfer funds to the card as if it were a bank account- theoretically that should work.