If you search a domain on godaddy.com and it is taken, they will tell you who owns it and you can even put yourself on a waiting list to take that domain. I love that site in that you can also check for your own site that you may want and get it for cheap. I think they can also be helpful in getting owner info in case you wanted to buy a taken domain name from a specific person or company.
Although Godaddy can be used as a source you will get too much commercial information as well as not all the info a WHOIS can offer. The owner of the domain can be found using something called a WHOIS search. As an example you can go to WHOIS.net and enter the domain within the first field. You will then be given the information about the owner and various contacts. If the owner has a private registration on his domain then it will be necessary to write to their anonymous address (it will be shown in the WHOIS information) and ask for ownership information. They can then choose to give you the information about them if they so desire.
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All of the above suggestions will obtain most all of the information that you are looking for. If you find yourself often looking for this type of information I would recommend downloading a program called "active whois". This can be found in many places including download.com. This program will search and store information about any site you wish and you always have it at your fingertips.