If you need help with GIMP, here are some people and places that will prove invaluable.
Homepage: http://www.gimp.org/
Manual and documentation: http://docs.gimp.org/2.8/en/
Blog: http://www.chromecode.com/ (Martin Nordholts' Blog)
Source code: git://git.gnome.org/gimp
There are countless tutorials and articles on the Web, covering various aspect of GIMP. You may search for specific task to do in a search engine (Google, Bing, Yahoo) and might end up visiting exciting websites with clear explanations on how to do it. GIMP users are everywhere, and their posts on the Web extends to picture albums, source codes, and also video tutorials. Following are some sites that are regular resources to GIMP users:
If you're really into learn how to make scripts:
If you are looking to get involve in GIMP, the following links are useful for you:
Official mailing list: https://mail.gnome.org/mailman/listinfo/gimp-user-list
Official forums: https://bugzilla.gnome.org/buglist.cgi?product=GIMP
Unofficial forums: http://gimpchat.com/
Official IRC channel: irc://irc.gimp.org/#gimp-users
User FAQ: http://www.gimp.org/docs/userfaq.html
The following unofficial blogs provide excellent inspiration and clever techniques to use GIMP:
http://www.jraleigh.com/my-publications/gimpfiretutorial.html (reference while writing the section on combining multiple pictures)
If you are twitter user, I must mention these twitter pages:
For more open source information, follow Packt at http://twitter.com/#!/packtopensource.