Hate to see posts go unanswered, especially by new or potential users … (happened to me too).
There is a CS-Mall software package, but I think it’s still in beta testing and has not been the developer’s highest priority. I really couldn’t tell you how far off an official release will be, but there are others interested in it too. I doubt it will be configured exactly like CafePress, but it is designed to handle multiple storefronts. The standard CS-Cart software is for a single storefront.
Concerning the “Jim” issue, there are multiple ways a customer can communicate this info to you. You can have them just add special instructions to the provided field in the checkout pages. Or you could create an option with text input (I’m pretty sure) as a part of the product page. It’s also not that difficult to create new data fields for the user to fill in and to save that info to your databse for your use later if the cart doesn’t have exactly what you need. Finally, you also have the option to track communications between you and your customer when they create an account.