You could then use that table to populate the list. When the list is submitted, you can add a recordset to tha action page of the form to filter a recordset based on the submitted value from the list to return the associated rate.
Store that returned rate as a session variable and add a shipping charge rule to the cart to charge a flat rate of the value of that session variable.
I believe that I followed your steps above, but would like clarification based upon my screen print. One thing that was unexpected was an error that we got when we hit ok on creating a new record set. please see attachments.
this is a link to some screen prints of what we're explaining above: cc3.php
Thanks
Jackie