From what I remember, oscommerce doesn't require any programming. You would have to setup the application, but it's not that hard. I've installed an earlier version of oscommerce, but I never utilized it.
At most, you would need to create a database, configure a few files so that the script has the correct username/password for the database, and maybe some permision changes. I was able to get this script working, so if you wanted to try it, I would help where I can.
Once the app is installed, you customize it through the web. (no dabling into PHP required.) Your products, pricing, and user managment is done through their admin section. If you're interested, I could setup a demo if you want to play with it? I don't know exactly what your "disiti" is...is that distribution list?
I also believe you can configure oscommerce to function with 3rd party billing systems such as 2checkout and billpay. I'll have to dig around on their site to determine what capabilities this has. I know some folks that host with us use this tool for their online ecommerce site.