I would probably agree with SS above, perhaps would be easier to have a few people do the "grunt" work, then you stylise it. Perhaps
@gregfindley for a design, some of his stuff is nice and clean, and then the code done by ^^ and then you can tinker and learn their system and extend it.
Otherwise the learning curve, from includes to full template will be akin to a brick wall with a 2 degree lean.
The option to still use includes still exists, if you make your "template" and then just use module includes to fill in the blanks. Put as much static / layout in header and footer, then use includes for unique blocks, to keep your index.php and other pages clean.
You could further this, by putting a switch in, called by index.php?about then use mod_rewrite to rewrite index.php?about to about.php, so it were all contained in a simple single file.
Not truly a template system, but an easy step. Anything else, and your asking for a world of pain and just need to dig deep.
header.inc.php
PHP:
<html><head><title><?=$title;?></title></head><body>
index.php
PHP:
<?
//pull from database
$title = $page['title']; // you could put $page['title'] direct into the header.inc.php.
//$page is also the array returned from the above database call.
include('./header.inc.php');
page layout
include('./footer.inc.php');
?>
footer.inc.php
PHP:
<div><?=$boiler;?></body></html>
The above were typed on the fly so maybe some typos
p.s. Maybe ask RobM if you can buy one of his old systems, maybe not wanting to sell his current work but maybe he has an old site/domain he'll sell you
