I don't want to put down a solution that is working well for you but M4 is a terrible choise for website management when there are so many highly capable tool kits that are dedicated to the task. As far as I know, there are no robost toolkits for generating a complete site of HTML page with M4. There's nothing wrong with rolling your own but that's hardly a productive use of one's time these days...

For a beginner I would recommend something like the Template Toolkit which is well documentend and has a large enough community around it to help beginners.

Cheers,

-J