wp e-commerce

I need wp-ecommerce to be able to edit orders, i already bought the wp-ecommerce manual orders plugin from vissir labs, but it doesnt allow me to manually enter in the price while entering the order for the customer. basically my customers’ shop will not be processing online but they do phone orders and deliveries, but they want the site to do hold all the orders and be viewable by person. Their products vary in weight and it isnt a strict scale, the prices vary depending on how much you order. Unfortunately this plugin i bought doesnt do that, it just allows you to make the order manually, but it constrains to the product prices, and it doesnt even account for the tables or the variations unfortunately. So now my question is, how can i manually edit orders that are going through manual gateway? OR

create products just for the backend of the site, not viewable by the frontend, so i can have products as different weight prices only in the backend? thanks