I'm trying to create a PHP script, which would be added to .php files (articles) on my website. This script would automatically add the article in question to a previously created database (and would subseqgently be used to timestamp articles). What would a script like that look like?

Do you want something like a CMS ? A form to enter your article and save it to the database ?

Here's a thread that basically does something like that. I think it will get you started.