If you are into photo editing and you don't want to pay for a program that you'll never use enough to pay for itself, check out GIMP.  I've been using it for some time now and have learned how to do many of the things I need to for web design work (including image maps). GIMP is free and not all that difficult to learn, as long as you are not afraid of tutorials.

Steven recently wrote an article listing 5 websites that will help you learn GIMP for free.  As Steven mentions, there are many articles here on MakeUseOf that provide GIMP photo editing tips (check out the "GIMP" tag), but there are also so many other GIMP photo editing resources out there on the Internet.

GIMP Guru

If you want a one-stop-shop for learning some typical image enhancing with the GIMP (many of the principles learned here also apply to other programs), GIMP Guru's tutorial page is the place to check out.  Learn how to do stuff like red-eye removal, converting to black and white plus reducing noise or haze all in this one place.

Grokking the GIMP

This site is actually an HTML version of a book written all about the GIMP.  You can order the actual physical book or you can use the online version for free.  Um, let's see, spend money?  Or free?  This book is a very thorough look at how to use GIMP so it could be a manual to come back to again and again.

Malgalin's YouTube Channel

When it comes to tutorials, sometimes video screencasts can really solidify what it is that you are attempting to learn about GIMP photo editing.  What better place to find screencasts than YouTube?  I ran across Malgalin's channel but a quick search on YouTube in general will come up with all kinds of GIMP tutorials.

GHUJ - GIMP Turoials

I'm not too sure about the name but the site is very cool.  It acts as sort of a GIMP tutorial portal of sorts.  Scroll through the very graphically based front page and find a cool effect you want to learn and click it.  You'll be brought to a quick description of the tutorial and a link.

Noupe.com's 30 Exceptional GIMP Tutorials & Resources

Noupe happens to be a site/blog all about different design aspects and software.  They have other tutorials besides just the GIMP.  What I found here was one specific article containing links to some very exceptional GIMP tutorials I think are worth checking out.

Learn how to do some cool effects like neon lights, recoloring eyes, and oil paintings and pencil drawings from photographs.  Oh, and for you Star Wars fans out there, they even listed a tutorial on how to do that cool lightsaber effect.

The Internet is a wonderful place to find out how to learn many different things and the GIMP is definitely no exception.  There is no way that in two articles we can possibly find all of the GIMP tutorials the Internet has to offer.  Please, by all means, add to this list in the comments.