Here are some of the FREE Control Panels for Web Hosting.
ISPConfig is one of the oldest free hosting control panels.
Webmin is more of a server administration panel. You can do most of the tasks in webmin.
Virtualmin is a plugin for webmin, that handles the web hosting part.
CentOS Web Panel
CWS one of the good free hosting control panels. It comes with everything you need to host your web site. Web Server (Apache, Nginx), PHP, SuPHP, MySQL, Email Server etc..
Sentora is an open-source web hosting control panel built specifically to work on a variety of Linux distributions. Sentora is licensed under the GPLv3 and is a separately maintained fork of the original ZPanel project. Sentora is developed and maintained by the original members of the ZPanel team.
The Vesta Control panel can be installed on a RHEL, CentOS, Debian and Ubuntu server.