There are three steps involved in finding out where a cell phone is located. The first step involves using your phone to call your own cell phone. The second step involves locating the nearest cell tower that the call was routed through. The third step involves calling that same number from another phone.
The goal of this process is to narrow down the location of the cell phone you are tracking. For example, if your target is in a large city, you will be able to get information about which area of the city they are in. This may be all you need to know if you are trying to determine whether or not they are near your home or office.
This process relies on knowing which carrier the person whose phone you are tracking uses. If they use AT&T, for example, then you will need to know what cell towers their calls are routed through. To find this information, call your own track cell phone number and location phone number from another phone and record what carrier it uses for service.*