Cell phone companies can locate a cell phone's remote location through a process called "pinging." What this basically means is that a cell phone company can pinpoint your cell phone's location by locating the cell phone tower closest to where your cellular device most recently sent and received a signal. This is a very useful tool for police and rescue workers in locating criminal suspects, people who need urgent medical attention and missing persons. It is illegal, however, for a civilian to ping a phone she does not own.
Determine the cell phone number you want to ping. Some cell phone companies may require the serial number of the cell phone as well.
Contact the cell phone provider associated with the cell phone you want to ping. Ask the cell phone company to ping the phone for you, and then provide the necessary information about the cell phone to the cell phone company. Cell phone providers have varying policies about how, when or if they ping cell phones. Most cell phone companies will not ping a phone that does not belong to you. The owner of the cell phone will have to personally call the cell phone provider and give the cell phone company permission to let you ping the phone.
Sign up for a cell phone tracking plan through your cell phone provider. This allows you to ping your cell phone automatically without having to contact your mobile service provider. For instance, Sprint offers a web-based application called "Mobile Locator" that allows you to locate your cell phone from your computer.