You might check out a few Launchpoint partners. I think you cannot use the marketo form for ecommerce, but you can integrate your ecommerce system into marketo. Here is one cart you could look at integrating http://launchpoint.marketo.com/kevy/1078-3dcart-cloud-integration-for-marketo
Josh is right. Marketo is not a PCI compliant tool. You shouldn't store cc info.
If your CRM is setup to handle ecommerce, it can be done within Marketo, but not the initial payment processing. It's probably better (and safer) to have an Ecommerce Platform+Payment Gateway that can post/webhook client data into Marketo for email sends.