the information inside of this JSP control

You aren't dealing with JSP; JSP is the back-end; you're always dealing with CGI.

I don't seem to be finding anything with the HTTP headers

What are you looking for? Maybe you should copy each and every header...

I look forward to an updated webspidering book with modern AJAX/JSP control scenarios to learn from

That would be a short book (or the same old book).

Add this to your code

#!/usr/bin/perl --

use strict;
use warnings;
[download]

and you'll get error because you're using $html before it populated. Also, there are no options in the html (that is created by javascript).