Where to put my advertising script?
 

I'm writing a PHP script to show some custom advertising stuff I need. Essentially my PHP script will return HTML that I'd like to display in the "ad_forumhome_afterforums" template. What I'm trying to figure out is how to "call" my PHP script from there using what's available in the vBulletin admin CP.

This may be helpful:
http://www.vbulletin.com/docs/html/o..._plugin_memory

From what I can gather, I'll need to create a plugin and specify a hook where my code will run. Is that accurate? I don't see a hook for "ad_forumhome_afterforums", just the template. When I attempt to insert my PHP code in that template, nothing happens.

You need to place a call in the template for that page, so find after the forum listing place a variable such as
$AdAfterForums or something like that.

In your plugin on forumhome_start declare your $AdAfterForums as what you want it to display as. When the page parses you'll find that it is where the variable was.