If you already have a html file from your design, and are using stock drupal, then the info on these pages (Convert any website layout or template into a Drupal theme - easily! and Assigning content to regions) of the theming guide will get you along.
In short, there are the following regions;
In 2004 I developed an affiliate web site in dreamweaver and I have done some minor maintenance on it since then.
Now the owner wants to be able to edit everything from his favorite coffeshop.
Anyway this is a great candidate for a straight migration from html to drupal.
He doesn't want to change the design of the website, actually a change is ok "as long as it is a bonus" but he really needs the ability to edit and configure, so this should be fun.
Main points are;