WhoisThisDomain - Domain name lookup tool that allows you to get information about domain registration from WHOIS server.
Whoisology - Connected database of whois records and whois history
DomainTools - Domain name research, including comprehensive Whois Lookup, Reverse Whois Lookup and Whois History.
WhoisAPI - WhoisAPI is the premier provider of freshly parsed whois data for domain names and IP addresses...
Bulk Whois API - Bulk Whois API is a provider of parsed WHOIS data in JSON with simple API, competitive pricing, top notch support, and more.
CubDomain - CubDomain.com is the site to check website's statistics, Information, Whois Record, Hosting...