There is a new example in my Demo Application showing how to create a simple shopping cart using Ajax and DHTML tipps from Carl Backstrom. This demo doesn't require a single submit and it shows how to utilize DHTML and Ajax to operate on collections. Since there is quite a bit of code and I am fairly busy at the moment, all the code is available only to those who have an admin login to my workspace.
You will find the example here:
Enjoy digging into it.