The IP WHOIS Lookup tool will provide you with the IP Address owners information. The IP Whois information contains data such as who allocates the IP (ie. ARIN, APNIC, RIPE, etc.), if the IP Address is allocated, IP Address contact information, and more. The results will also show other important information like how many IP Addresses are in the block or blocks assigned to the owner of the IP you're referencing.
If you have any questions about the IP Address WHOIS Lookup tool or the results, please check out the IP Address WHOIS Lookup Forum.