When I maximize a window in Ubuntu 11.04, the close, minimize and maximize buttons change to these nice ones
Where are they located on the filesystem? I would like to build a theme out of them but want the originals.
The buttons in question for Ambiance are in /usr/share/themes/Ambiance/metacity-1. Each theme has it's own set using the same file names. You can edit these png files. I changed mine from orange to a shade of blue I liked. The system uses a base name like "close" and appends let's say "_focused_prelight.png" to get the file name for the state to display.
Those icons get painted by Unity as fallback if the chosen theme isn't Ambiance or Radiance, so you won't find them in any directory.
they'll be in the theme directory. depending on whether this is a theme you installed, or one that came as a default with the system they'll be in:
typically window buttons appear in the
metacity directory, rather than the gtk directory.