I'm looking for skilled website security Pro to test my website security holes.

I recently noticed some file intrusions attempts to my website. Although they have been stopped by the firewall, I need some help to make sure there will be no real intrusions in future. I have received some emails using my domain email addresses which have been sent out of my server (spoofing the domain). As this is the first time I realized it's actually quite important to secure my domain. The website uses Joomla and MySQL database and some components such as Jomsocial, Kunena, Easyblog and Acymailing. Just in case, I were not able to provide you the necessary information, My programmer would provide all the information.