loan question

[jerri]

Hi, I loaned someone $1,200.00 in Nov. 06. They promised to pay $100.00 a month. They paid back $500.00. The last payment I got was in March 2007. I had a loan agreement typed up & it was signed by both of us & notarized. I know I can take him to small claims court, but my problem is that all I have for his address is a post office box & I think I need a physical address to serve him with a warrant of debt. I do have his drivers license number. Is there a legal way for me to obtain his physical address? Thanks alot for your help!!