I'm looking to add some custom functionality to a VB installation, but I can't for the life of me find any place to drop code into the VB structure. I know most of the code is pulled from the database, but where can I find a template file, etc where I could add my own code module {like if I wanted to add, say, an open source chatbox to the footer]?
vBulletin is written in PHP, so it should just be a matter of finding the correct .PHP file and adding your code there.
Have you tried looking in footer.php?