Trying to find a dead-beat father who is running from the system. 
Although, I do have his current cell phone number.  I would like to know
the best, and CHEAPEST, way to find out the address linked to this
cell phone account.  I know there are sites online but they all charge
soooo much.  How do they get their info to start with and what would
be a free or cheap way to get the info myself?

http://www.411.com/reverse_phone  you can find the carrier and the
city here, if that helps.