In order to find a lost mobile phone, you should very first narrow down the achievable areas where the phone could be located, especially if it really is misplaced in your home. If you nevertheless cannot locate the lost phone, trying to call the phone from another one and listening out for the phone's ringtone would be wise especially if the phone is usually in the vicinity. Do check more information about IMEI Tracker Software and IMEI Locator.
However, trying to locate a stolen cell phone which was lost somewhere else additional than at home might require a more technical approach. The police could be informed by you and your service provider to help you locate the mobile phone. One should however ensure that the cell phone is not within ones area of operation such as at home or the office. You should also be having all documents related to your telephone and disclose the required details to the service provider and they should be able to upgrade you if someone else uses your SIM. Some are even able to inform you if the person in possession of your phone runs on the different SIM in your telephone.
GPS could be used to find a lost mobile phone if it is GPS enabled. The GPS technology enables one to pinpoint the exact location of the telephone, through the internet. This would however, required the owner to have installed tracking software on the phone as it would be quite challenging without the tracking software. Smartphones can also be located making use of different internet applications, with certain applications sending a message to the phone even. The message could include a way of returning the phone to the original owner since its area is already known.