Registrar Directory & Root ZoneDatabase
http://www.internic.net/regist.html
http://www.iana.org/domains/root/db/
Whois
http://ping.eu/ns-whois ( Ajax , Update Info & DNS nhanh )
http://www.aplus.net/cgi-bin/whois.cgi ( Ajax , Update Info & DNS nhanh )
http://ajaxwhois.com/ ( Ajax chỉ yếu để check nhanh available, thêm dot ở My preferred extensions)
http://www.ajaxlookup.com/
http://