Many of the sites I do are php only which offers many advantages. One is the copyright notice can be updated programmatically instead of manually. Here is the snippet of PHP code I use (the define is put into a config file):
define(STARTCOPYRIGHTDATE, "2009");
$thisyear = date("Y"); // YYYY
if(0 == strcmp($thisyear, STARTCOPYRIGHTDATE)) $gcopyrightdate = $thisyear; else $gcopyrightdate = STARTCOPYRIGHTDATE . '-' . $thisyear;
If the site uses html files, there are a few ways to do this. One is to use a server side include file. The include file has to be manually changed then uploaded to the server. Once there, all files using it are up-to-date. This is nice because every file on the website does not have to be updated.
The last way I mention is to use an include file or, if you have a template, put the copyright notice in it. The drawback is every file will have to be uploaded to the server.
Doug