Hi,
I've installed ISPConfig on several OpenVZ systems and never had any problems regarding OpenVZ. Your problem is not OpenVZ related, your problem is that your linux distribution is just a bare linux system without any tools.
For centos install, please have a look here:
http://www.howtoforge.com/forums/showthread.php?t=2892
The fedora howto mentioned in the thread can be found here:
http://www.howtoforge.com/perfect_setup_fedora_core_3
http://www.howtoforge.com/perfect_setup_fedora_core_4