Win32Whois (Freeware) - small, fast and powerful whois client.
Win32Whois is a free, small and efficient tool that lets you retrieve registration information for a particular domain or website. It takes URL, hostname or IP address and will generate a detailed report listing all the available technical and contact information it can find. The generated report can be saved as a file or used to track down website owners, administrators or spammers.

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