Anyone help me with a reverse cell phone lookup?

Anyone help me with a reverse cell phone lookup?

I need some help with looking up a cell phone number that is sending random unwanted text messages to my cell phone. I have narrowed it down to a city, Janesville, WI, which is only a half hour from me, but need a name. Can anyone help me? The last one was very strange, and scared me a little bit. It was of a man holding a handgun, just his hand showing. I am not sure why this would be happening, but it is very strange. Anyone have a reverse look-up account that they can use to help me? The number is 608-718-4797.