Method: Use a friends phone to call the unknown caller
If you want to find out who called you, but don’t want them to know that you are trying to find out who they are, a great idea is to use a friends phone to call the person and get to voicemail. Once in voicemail, if they have a customer greeting it should say who they are, and to leave a callback number. This will give you an idea wether the person is male or female, and if they have a regular phone number or a Google Voice number too.
The point in using a friends phone is that the other person won’t be able to find out how you reverse phone called them, using a friend ensure that you remain anonymous. Using this method to reverse cell phone lookup for the number in question ensures that you find out who called you originally.
You can also use a service online to call a persons phone for you, and it will go straight to voicemail. A common website an be found by performing a Google search. Many websites offer this for free or for a small charge.