This is year 2011 and I think that you should know that what you see in the cinema is not far from the reality. Authorities can track each and every cell phone location as well as location history. Which means that they can track all the ways you cross. Scary? This is not the end, having your cellphone number, they will find out your personal details with ease. When they have your personal details such as name, surname and SSN, they will be able to retrieve all the information government keeps about you, such as public records - marriage, birth, death, criminal but also not public such as information from IRS, hospital history and so.
As you see, there is no big difference between what you see in the movies and what is possible for the Government. The good thing in this is that you can perform a few actions mentioned above on your own. You will not of course gain access to any private or secret files, but you can obtain public records using only a cell phone within a few simple steps. There is no problem to locate the cellphone location. However, you should bear in mind, that this is not the current holder's position but the address that were given for registration the cellphone.
All you will need to do, is to find a reputable cell phone lookup company, which will eagerly provide you will the data you need. Forget about all those free services which you will surely stumble upon when looking for a decent company. These cost-free solutions will give only basic and usually inaccurate data which are completely useless in most cases. That is why I strongly advice you to get a paid service and don't worry about the accuracy of the information. Of course, if you're not satisfied you can always get your money back, depending on the moneyback policy of the company of your choice.
To summarize, as an ordinary person which has nothing to do with authorities you are still able to track down any cellphone number you want. You will be still able to retrieve the owner's name, address and public records as well. But always bear in mind, that using the data retrieved in such way to perform any criminal activities may quickly get you behind bars. However using such data for legitimate purposes is 100% legal and you don't have to worry about any consequences.