Many times a first and last name will be enough to find a phone number. However, the more information that you have about a person the easier it will be to find their phone number. A lot of times when a person is looking for a number, it is because it had shown up on their caller ID or on their credit card statement as a charge they did not recognize. I know a person who had a problem where Amazon.com made an unauthorized charge of more than $300 to their credit card, and because he could not find a phone number, he had no way deal with this problem that needed immediate attention. He finally did a search on Google and found somebody who posted the Amazon.com customer service number to his website.
The on line phone books will help you to find a phone number when you provide a name and/or address of the person you are looking for. It is always worth trying all of the on line phone books if you don't find the information you are looking for. You may come into a situation however that either the name or number is private or they simply do not have a home number but a cell phone number.
Cell phone numbers are not listed and as a result you cannot just look into the phone book and find a cell phone number. To the resourceful, however, there are other ways in which this information can be had. A volunteer directory is yet another option to find a cell phone number. People voluntarily list their cell phone numbers and other contact information in a volunteer directory, you can find these directories by doing a search on the Internet. You can also do a paid search by going to the website listed at the end of the article or doing a search for paid cell phone lookups. Their are many resources, usually paid to be found on finding out the owners of cell phones.
You may also consider looking on social networking websites such as Myspace and Facebook, these are becoming very good investigative tools because of their massive membership statistics. You could go to either site and do a search for the phone number, you may get lucky and something comes up. Many times a member will post their phone number on the comments section of the users page. It would only be natural that it would show up in a search you do for the number in the respective websites.
If you have tried to look for the number in all the major search engines, the major social networking websites, then you may resort to using a paid service to find the number you are looking for. They are usually worth the costs, especially if you just have an itch to find out who a number belongs to. You will always get more detailed information than you could from an on line search as well.
Using the above methods will surely quench your thirst for finding out who the number belongs to that called you at two in the morning or the cell phone number that does not have a name attached to it. It just takes patience and a little perseverance.