You may be dealing with a caller that could endanger you or your family, so a situation like this is when it would nice to have a free directory where you could easily trace where the call is coming from. If your looking for a reverse cell phone number lookup directory then you need to know that there are many choice that you should consider.
By using the online residential phone number search services, you have access to telephone information from all over the country, and from other countries. Normally, these are used to find someone's number by first putting in their name, and then their location. If you were to get a call from an unknown number in the past, you could not do much other than call your phone company to see if they can give you more information.
Free directories will only give you landline numbers, not mobile phone numbers. This is especially helpful if they have a map or directions. Reverse phone directory will give you not only the person's address, it will also give you their name, location and current address, phone carrier, court records, criminal histories, birth records and other legal files.
But if you want quick and absolutely reliable results, go for the paid services that provide directories for cell phone numbers. All you need to do is type in the number into the box to get started.