when you install new programs onto your computer through RMP bits and pieces are storred all over your computer, not in one spot like windows. You can change the default installation directory by using some of the rpm switches
/usr/bin is where only binaries are storred (bin short for binaries which are much like exe files in windows), so all files in this directory will be executable files.
other directories like this one are /bin, /sbin, /usr/local/bin etc etc etc
should show you them all.
what you were doing when changing the icon looks right, make sure you pressed ok and not cancell.