ASP.NET : how do I develop a cart checkout page?

Hi, I'm working on converting an ASP site to ASP.NET using vbscript. The page I'm trying to rebuild in asp.net is a confimation page which lists items in a shopping cart. Items are grouped by vendor, each vendor is assigned as a seperate order, and each group can have a memo item attached along with the option of adding custom items (with buttons that open special editing screens and the items are displayed with each grouping). The current page builds several records sets and loops through the data to display it on the page, but now with .NET, I'm assuming I'm going to be building this page using a GridView with headers and footers to display group data and display the custom info. OK, where do I start? I've been struggling with GridViews as it is and I've only done a few things with footers, but I'm not sure were to begin with this one. Any suggestions, examples I can start with? Thanks!