It’s been a long time now that it is possible to create PDF files from PHP, there is already a series of functions in PHP to do this. You can find the information on creating PDF documents read the following article from zend:

http://www.zend.com/zend/spotlight/creatingpdfmay1.php

If you need a ready to use PDF PHP Library, you can find it here:

http://sourceforge.net/projects/pc4p/

More resources on PHP Howto’s in alt-php-faq.org.