Printer - PDF format: How can I change the header info and add page count on the footer?
The Print module uses a separate template for the print, email, and PDF versions of a page.  You would need to implement a hook_preprocess_print() to set up some addtional variables, and then duplicate print.tpl.php into your theme and use your new variables (and/or change the markup in the template).  The default template file is rather well documented, and explains what is possible.