To create it in your master style you will need to be in Debug mode, the code for who's online is entered in to a plugin using the plugin manager>add new plugin
Ok, I modified my config.php and entered debug mode. I see that it now lists all the Templates used and Included Files, Hooks, etc. Ok, now what? I see in step 2 of the instructions that it provides HTML code for a template. Do I simply make a file with that code in it, or is there some other process I must follow? If I create this template for my new page from a stand alone editor, I know the file name is case sensitive, but what file extension, if any, do I give it (for example, in UBBThreads, which i'm moving from, templates had a .tpl extension. I guess what I'm asking is can you break down Step #2 in the above linked instructions and walk me through HOW I create a template for a page and put it where it needs to be. I got step one ok - created a page and uploaded it to my root. Sorry for the dumb questions, but I'm new at vBulletin and it seems to work quite differently from what I'm used to.
EDIT: Ok, stand by - I think the light bulb just went on. I found where I can "Add New Template" based on the "MASTER STYLE" in the Admincp. I copied the HTML in your example into that Template editor, then went to my "mypage.php" script and viola! It worked!
I'll play around awhile more - don't go too far - I may need you again!