Order Form Customization Help Really Needed

Hi, I REALLY need help doing TWO Things:

1. Create a Single Page Order Form Similar to the HostGator Shared Hosting ORDER FORM.

2. I need to be able to create an Order Form Page, where I take the clients DOMAIN NAME only and then push them directly to CHECKOUT - where number of years, coupon, etc is all PRE-CONFIGURED.

Can anyone please direct me to where I can find the info to do these things please :)

Any help would really be appreciated.