WHOIS commands cheat sheet
Getting information on domain name
whois anyplanet.org
Getting data to an IP address
whois 8.8.8.8
Getting data about some specific WHOIS server set up by an ICANN
whois -h whois.verisign-grs.com google.com
Getting Information about a domain name from a specific registrar
whois -h whois.iana.org com