Introduction to The Gimp - Tutorial for beginners who are not graphic artists, introductory guide on how to use the program. - http://members.cox.net/wcommerc/the_gimp/the_gimp.shtml
GIMP Developer FAQ - Answers technical questions. Provides other online resources for IRC and email lists. Not updated recently. - http://www.rru.com/~meo/gimp/faq-dev.html
GIMP User FAQ - GIMP User Frequently Asked Questions - http://www.rru.com/~meo/gimp/faq-user.html
How to Make an A4 Poster Using the Gimp - The tutorial is composed of five lessons each broken up into particular areas of gimp expertise. The tutorials are designed for newcomers to the Gimp, and to Linux. By Kester Clegg. - http://www.ylug.cwc.net/Tutorial/Poster.html
Scheme Tutorial for Gimp - This document will try to be a brief introduction to Scheme, just teaching the essentials in order to write script-fu scripts, by Dov Grobgeld. - http://imagic.weizmann.ac.il/~dov/gimp/scheme-tut.html
Kevin Turner - Writing a GIMP Plug-In - http://gimp-plug-ins.sourceforge.net/doc/Writing/html/plug-in.html
Mini-Howto - Document describes the basic configuration of Gtk Themes for the GIMP running under Win32 systems. - http://www.rixsoft.com/gimpwin/gtk-themes.html
Creating A Web Plaque: A GIMP Tutorial - This tutorial takes you through the process I used to create the so called web plaque. - http://www.disordered.org/GimpPlaque.html
Nem W Schlecht - Tutorials that covers making a 3d Button, and easy animations. - http://empyrean.lib.ndsu.nodak.edu/~nem/gimp/tutorials/
Tileable Textures - Making tileable textures with gradient brushes - http://adrian.gimp.org/texture_tut/
Dov Grobgeld - A Tutorial for Perl Gimp users. - http://imagic.weizmann.ac.il/~dov/gimp/perl-tut.html
Creating Animated Brushes (Image Hose) - A Gimp Image Pipe allows you to spray out series of full color pixmaps. To make it more flexible, the order the images are painted onto the campus can depend on direction, angle, speed, or other factors. - http://adrian.gimp.org/gimppipe/
Gimp Perl Tutorial - A tutorial on using Gimp Perl scripts for Gimp 1.2. - http://www.alexharford.com/perl.html
Grokking the GIMP - by Carey Bunks, This is actually a book. You can either download or read free html version online or buy the hard copy. - http://gimp-savvy.com/BOOK/index.html
Stefan's GIMP Site - GIMP is powerful enough to be used by professionals, but still free. Pictorial tutorial. - http://hem.passagen.se/sberge/gimpdemo/gimpex.html
Obscura - A tutorial about creating text with an 'outlined text effect'. - http://www.obscurasite.com/artstuff/tutorials/gimp-text-outline/
Beginners Guide to The GIMP - A tutorial for complete beginners with The Gimp, explaining most of its basic (yet not always intuitive) functionality. - http://bachue.com/alejo/gimptutorial.html
Drawing with the Gimp - Larry Ewing's drawing with the Gimp. - http://www.isc.tamu.edu/~lewing/gimp/
Gimp Tutorials Pointer Page - An extensive list of tutorials from many different authors. - http://empyrean.lib.ndsu.nodak.edu/~nem/gimp/tuts/
GUG - Tutorials - Assortment of tutorials from the Gimp User Group. - http://gug.sunsite.dk/?page=tutorials
GIMP Tutorials by Zach Beane - GIMP tutorials covering vignettes using quickmask, desaturation, punch-out, and alien glow. - http://www.xach.com/gimp/tutorials/