You can offer up a shareware version of your software only, limited by whatever methods you chose, and leave it at that. Or you can give them a full, unrestricted version, let them create a shareware version for general distribution using their own licenses copy protection schemes, and sell your unrestricted copy to those who like the shareware version. That's entirely up to you through Cnet's Merchant Services.
Hope this helps,
I don't understand one thing on download.com. Upload.com offers the free http hosting service. I sell my software over Shareit.com. All people that find my software must buy it over this provider and download it from them after purchase. But if I give it to download.com to host it...what does it that mean, that download.com will put it on their site and let the users download it for free, or is the http hosting meant only for the trial versions?