Note: The correct title of this article is dvbutils. It appears incorrectly here due to technical restrictions.
DVButils is a collection of, well, DVB utility programs. In various places it is also called dvb-apps or dvbtools.
Most Linux distributions have a dvbutils package. For example, with Debian or Ubuntu install the package with
apt-get install dvb-utils
The definitive documentation for dvbutils is on the LinuxTV wiki but you can also see some documentation in this wiki at the dvb-apps page.