There are a few tips and tricks to finding where ou lost your phone. If you suspect that you tablet, laptop or phone has been stolen, you should contact the police and your phone carrier. If you cannot get the device back, you should make sure to secure your private information immediately. If it has just been lost, try to call your phone from someone else's phone. If you have programs like Skype installed on a tablet or computer, you can try calling that too from another phone or computer as long as you are signed in on the device.
If it has been stolen, you will need to change the passwords to any social media or bank that is installed on your phone. Also consider changing your password for your Google accounts. Google Account password. You may want to install a passcode on your phone in the future which isn't completely secure but will stall the person trying to access your private information and give you time to change any sensitive data.