My goal will not be to review all the ZenPacks currently available or try to anticipate your exact monitoring needs. Rather, we're going to walk through the process with a relatively simple example to monitor websites with the HTTPMonitor ZenPack.
Find ZenPacks online at http://community.zenoss.org/community/zenpacks.
Many ZenPacks are community contributed and are reviewed by the Zenoss team prior to being made available for download. Still, it would be wise to install a ZenPack on a test installation of Zenoss Core before you commit an unknown change to your monitoring environment.
As of December 2010, Zenoss Core 3.0 has been out for six months, but not all ZenPacks are compatible with the latest version of Zenoss Core. Check the ZenPack download page to ensure 3.0 compatibility.
Installing a ZenPack consists of three general steps:
Download the ZenPack from the Zenoss ZenPack Project Site.
Install the ZenPack.
Configure the devices to use the ZenPack.