http://wiki.openvz.org/OS_template_cache_preparation is where to start.

1. To see which templates are available, run
   

   # yum search vztmpl

2. To install some of the templates, run

   # yum install vztmpl-XXX [...]

3. Run the vzpkgcache utility; see the vzpkgcache(8) man page for details. It will create or update the caches of all the templates for which the corresponding metadata exist.

   # vzpkgcache centos-5-i386-minimal
   

4. Verify that you have installed it:
   

   # ls -lrt /vz/template/cache