How can I put up a cPanel icon that accesses a (local) home directory file?

I know how to develop then install a custom icon in cPanel, which will then link to a single file on the server.

But what about making a link for the icon which will open a file that is within that specific cPanel/account owners public_html directory?

I would gather that this is possible with some sort of address link, like:

<a href=$userID/www/filehere.html>img src="icon.jpg"></a>

... but I'm really green at this kind of development work, and after searching around all day, I can't quite figure out how to come up with a link that is just and only for that specific account owner.

Anyone?

Thanks very much!