I'm trying to do a whois lookup, but I get hit with this error:

-bash: whois: command not found

Where can I get a new copy of whois (for centos)?

# locate whois
/usr/libexec/webmin/bind8/whois-servers
/usr/libexec/webmin/bind8/whois.cgi
/usr/libexec/webmin/bind8/images/whois.gif
/usr/libexec/webmin/blue-theme/bind8/images/whois.gif

It's in a package called (surprise, surprise ) whois.
Just install that package.
cheers,
jdk

# yum install whois
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
* rpmforge: apt.sw.be
Setting up Install Process
Parsing package install arguments
No package whois available.
Nothing to do

It's called "whois" in debian-based distros. I don't know what it's called in centos or else you don't have the correct repos in your sources.list. Do a google for centos who is and you should find it easily enough.
Ciao,
jdk

Finding the package it's in is not easy, I haven't had any luck on google..

What about jwhois for centos?

I noticed that as an option to install, is that just a clone of whois?

The only Centos servers I have are in production, or else I'd test it.
http://www.gnu.org/software/jwhois/
http://linux.about.com/library/cmd/blcmdl1_jwhois.htm

jwhois - client for the whois service
SYNOPSIS
jwhois [ OPTIONS ]... [ QUERY ]
DESCRIPTION
jwhois searches Whois servers for the object on the command line.

The host to query is taken from a global configuration file, a configuration file specified on the command line, or selected directly on the command line.

Looks like it...

Hi,

From the console as root what do you see with 'which whois'? As your user if not in your path; '/usr/bin/whois'?

[root@xxx sysconfig]# which whois
/usr/bin/which: no whois in (/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin)

jwhois is a clone/adaptation of whois. Should be just fine.

Actually, I've run into a number of packages that happen to be clones of originally named packages. And what the distributors do is link the original name (i.e. whois) to the actual binary (i.e. jwhois).

[root@localhost /]# yum install jwhois
Loaded plugins: fastestmirror, refresh-packagekit, security
Loading mirror speeds from cached hostfile
..........
Setting up Install Process
Resolving Dependencies
--> Running transaction check
---> Package jwhois.i686 0:4.0-19.el6 will be installed
--> Finished Dependency Resolution

Dependencies Resolved

==================================================================================================== ==========================================
Package Arch Version Repository Size
==================================================================================================== ==========================================
Installing:
jwhois i686 4.0-19.el6 base 103 k

...........
Package: centos-release-6-2.el6.centos.7.i686 (@anaconda-CentOS-201112130233.i386/6.2)
From : /etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-6
Is this ok [y/N]: y
Running rpm_check_debug
Running Transaction Test
Transaction Test Succeeded
Running Transaction
Installing : jwhois-4.0-19.el6.i686 1/1

Installed:
jwhois.i686 0:4.0-19.el6

Complete!
[root@localhost /]#