in the source directrory.
This will probably not work (!) as hardly any supply uninstall info.
You could run make again and examine the output to get a list of files/folders installed.
You could use -prefix on your make when installing (eg -prefix=/some/place/) so you know where it's installed, too late this time I guess
Could also check for a .directory the home of the user that ran the installed app - only works for some stuff but would give you file locations etc