I am looking for a website/tool that will do the following:

If I have a domain name like www.abc.com, I want to see the other
domain names that are owned by the same company that owns www.abc.com.

How can I look this up?

Hi there, 
 
I am aware of four services that offer a search by owner (aka organization). 
 
1) Dialog Select 
http://openaccess.dialog.com/ip/  
Click on domain names in the left column and you will get to a form
for searching Whois by owner names. It costs $3.65 to view each
record. Alternatively you can cut and paste the resulting domains and
use a free Whois service. My favorite is a nifty little piece of
software called GTWhois:

Geek Tools Whois 
http://www.geektools.com/tools.php

 
2) Saegis 
http://www.compu-mark.com/Frameset.asp?reference=03-01.02-01.03-01&lang=en&country=0
Subscribers can look up domains by owner for roughly $1 per record.


3)MarkMonitor 
http://www.markmonitor.com/ 
Subscription based. Also available via Lexis Nexis 
 

4)Verisign Referral LDAP 
http://www.ldap.verisignlabs.com/  
Click on Organization to search for a name, and find out the domains
they own. Only works for domains registered via Verisign.


Best wishes,
robertskelton-ga

thanks for quick answer

Try http://www.whois.sc/ 

Most companies that own multiple domains will host them on the same
server, and with a silver membership in the above site, you can search
for a domain and then view all the sites hosted on that particular
server.

I use the above tool all the time, but since you have to pay for it I
didn't want to 'answer' your question because there may be a free
version out there that I'm not aware of.

Good luck though!