I met this person online and I want to know who they really are and I have his cell phone number but I don't want to pay money to find out his name. Does anybody have a free online site? Thanks!

Not really and depending on who the service is with, you may not ever really know even if you pay. For example, before she passed I bought my mom a cell phone at walmart, I bought minutes on a card no one knows who it is registered to.

I just bought some phones for our family from one of the major carriers, and did use my name but I could have used any name, they never asked to see a ID. I pay for the phone min at the store in cash, so no need to have any ID.

And for many carriers even if the carrier knows who has the phone, it is not always available.

So from merely a phone number you have no way to know. Over time you talk to them find out where they work, and more personal info.