How do I pay with credit card on Ebay? not PayPal?

I am not using PayPal. A particular seller accepts credit card. After going through the purchase pages, Ebay told me to contact the seller to pay with my credit card. I contacted the seller, but have not received a reply. What I'm wondering is, why doesn't Ebay have an automated credit card system, akin to their PayPal system? Furthermore, what could the seller possibly ask me to do? Are they going to ask for my credit card information; or will they link me to a secure credit card transfer site? I'm apprehensive about sending my information through an unsecured system like plain old email.