My brother has been missing for two months now . The police won't do anything because he was not taking by forse. I have looked up his cell number, but it give me the address I already know. When I call his cell it goes to mailbox. How can I locate the cell phone. I don't have much information just the number

You can not locate the cell phone on your own, And the other cell phone will have to be turned on and being used, not voice mail.
The police can fine what cell tower it is being used from.

Does he work, is his bills being paid.
How do you know he was not taken by force, more details please

Also the cell company can see if there was any recent use on the phone, outgoing calls, etc. is this person over 18, I assume?