the information from the checkout page is stored in session variables when the checkout page posts to the confirm page.
make sure the hidden form element on the confirm page is named exactly the same as the text element on the checkout page.
On the confirm page, go to the server behaviors panel and click the plus button. Select eCart -> General -> Set Session value.
For the trigger and value, click the lightning bolt and selct the hidden form element from the form list.
Set a unique name in the name box.
You can reference the session variable on the success page.