Where are my files?

Hi newb here. I bought a MacBook pro from a friend and recently changed from his home directory name to mine (reference: OS X: How to change your account name or home directory name). When I changed it, I noticed that the files are gone and the desktop went back to the way it started. BUT... when I search for files like "megadeth", it still shows up under my friend's name, but it is nowhere to be found under the new name. Any advice on how I can retrieve the files and put it under my name? Thanks.