Where can I get online credit cards?

If you mean credit cards that are restricted to online purchases then you need to contact your bank for details. We have one that we use that holds a fixed amount for a fixed period of time and we tell the bank how much to put on the card, if the online store doesn't take the money within a set period (usually 12 hours) then the money comes back to me and the transaction fails. No one loses and there is very very little chance of fraud.
If you mean arranging to get a credit card (visa, access, mastercard, etc) online then I'm afraid that to the best of my knowledge you can only do that through your bank in person or possibly (probably) through the credit card's website.