change YOURTHEME to your theme name and clear the cache.
The real Question why should you use static HTML file for your homepage? I would create some article or view for homepage and change it as I like with theming... It is much easier than any other alternative.
If you have specific HTML page that it is on the server and doesn't generated from Drupal, the most easy way is to use Drupal goto.
How to do it? open your template.php and search for page_preprocess function it should look like that:
change YOURTHEME to your theme name and clear the cache.
The real Question why should you use static HTML file for your homepage? I would create some article or view for homepage and change it as I like with theming... It is much easier than any other alternative.
For Drupal 7 you need to use page--front.tpl.php
If your theme doesn't have a page.tpl.php that you can copy, then copy it from your base theme if you are using one or:
This should be placed in your custom theme folder in (assuming this is not a multisite):
I tend to structure my themes as follows:
But it doesn't really matter where it is, it will be picked up after a cache clear.