If you are looking for images to practice Gimp Techniques (i.e.,
selections) there are some awesome pictures at the US Fish and
Wildlife Service web site. For example:
Start Here: http://images.fws.gov/
On left-hand side, click "Or Browse The Library"
Scroll to "Perching birds;"
NASA, NOAA also have some tremendous images. Who doesn't like
birds, fish and planets and stars :-)
Gimp-user mailing list