Custom Payment Module - osCommerce

Hi Folks, I was wondering if anybody would be able to help me with this and I am even looking to pay if they can? I am looking to create a very simple Payment Module for my osCommerce store and in my view it's a very simple idea, I just don't know where to start and must: 1. The Order must be inserted into the Database before a customer reaches the new Payment Module. 2. Just redirect to another Webpage of my choice that I can change if required in the future to a new address for the customer to complete. It's as simple as that! Is it easy to implement? Cheers!