Whois lookup is a useful tool to check the status of ownership of a domain name http://www.domainwhitepages.com/ hopefully useful
simple way to change the proxy ... This one from the list of proxy sites _http://www.ip-adress.com/proxy_list/
I offer a private api that will let you query bulk whois. Ip issues are handled on our end so no issues with that. I will write you a custom macro to use our api for you. Message me here if you need my help.
Whois lookup is generally a free domain tool to get the detailed information of a registrant along with the IP address, name servers, etc.
You can try this: www.wlooker.com (MX Records, TXT Records, IPv6 Records, RDNS Records, SOA Record, Whois Records, IP Address Whois Records, Domain Nameserver Information,Traffic Report, etc)