How can i find someone's home address?

How do I find sombodys home address a know the name a number but they moved and never told me where to they owe me some money and I need to find out where they live any help

not sure im doing the same thing my friend is supposed 2 give me my 100 back but he moved to a different school around here

Try looking on whitepages.com and type in their name and any other info you know. If they have a listed number then it should show up in the search results.