T-shirt design

Hello! I was looking for something similar a few weeks ago. I will give it another try. I need something similar to spreadshirt.net. I need the product design and shopping cart/order part (no affiliate or other stuff). I need to be able to populate the shop with different products (not only t-shirts). And I need to be able to set the available options for each individual product type. I need it to be built in ASP or ASP.NET and probably flash for the design part. No PHP solutions are interesting. I am looking for a prebuilt solution where I can se a fully working demo before I place an order (not only a screenshot). BR/Peter