Add Extra Fields to my Eshop Wordpress Plugin

I am using the "eshop" wordpress ecommerce plugin. Unfortunately the checkout page has set fields and I need to add some. Currently the plugin doesnt allow an easy fix and it has to be coded into the php code. Once the order is processed the info from the checkout page gets emailed to me, I believe the customer, and gets added to the dashboard. I would need the new info fields to do the same as well. Right now the fields are: First Name Last Name Email Which are all required. I need the Following (* indicates required): First Name* Last Name* Email* BHW Nickname* Website URL* Website Title* Keyword 1* Keyword 2 Keyword 3 Niche* Website Description* Plugin Info: [login to view URL] [login to view URL] Please be proficient in PHP/Wordpress Plugin Editing