Official Gimp Tutorials
A set of over fourty tutorials featured at the Gimp.org web site.
http://www.gimp.org/tutorials/

GUG Tutorials Page
Over fifty tutorials found at the The Gimp User Group (GUG) web site.
http://gug.sunsite.dk/?page=tutorials

GIMP Tutorials Pointer Page
A page with pointers to a series of tutorials. Most work, some do not. Many are for older versions of GIMP.
http://www.surveillance-video.com/gimp-feb-2010.html

SAMS Teaching Yourself GIMP in 24 Hours
Older textbook hosted at a Russian free books web site.
http://freebooks.by.ru/view/GimpIn24h/

GIMP Tutor Page
A short series of mostly text effects tutorials.
http://at8.abo.fi/~mwikholm/com/gimp/tutor/

GIMP Guru Tutorials
GIMPguru.org is a web site devoted to use of GIMP for photo editing. The site has a series of about thirty tutorials.
http://www.gimpguru.org/Tutorials/

Gimp Tutorials
A nice series of five tutorials including how to draw a paintbrush.
http://tigert.gimp.org/gimp/tutorials/

Gimp Stickman Tutorial
A nice overview style tutorial including drop shadow, etc.
http://www.ufocomes.de/files/basegien.html

Flame Fractal Tutorial
Very detailed tutorial on making flame fractals.
http://www.arcanefractals.com/tutorial_part1.shtml

Photo Touch Up Tutorial
A very detailed look at fixing photos with contrast and other issues.
http://www.geocities.com/SiliconValley/Haven/5179/

Text Outline Tutorial
How to put a strong outline around text.
http://www.obscurasite.com/artstuff/tutorials/gimp-text-outline/

3-D Button Tutorial
Simple Tutorial on making 3-D web buttons.
http://www.kci.net/~jesse/gimp/tutorials/buttons/

Fire Effects with GIMP
Detailed flaming text tutorial.
http://www.linuxfocus.org/English/November1999/article112.html

Remove One Color
How to move a color, or color range, from a photograph.
http://bitbit.org/cms.php/remove_one_color.html

GIMP section of deviantart.com
Deviantart.com is a place where amateur artists share information and artwork. There is the GIMP user section of the web site.
http://the-gimp.deviantart.com/