GIMP is a cross-platform image editor available for GNU/Linux, OS X, Windows and more operating systems. It is free software, you can change its source code and distribute your changes.

Whether you are a graphic designer, photographer, illustrator, or scientist, GIMP provides you with sophisticated tools to get your job done. You can further enhance your productivity with GIMP thanks to many customization options and 3rd party plugins.

Apache OpenOffice is the leading open-source office software suite for word processing, spreadsheets, presentations, graphics, databases and more. It is available in many languages and works on all common computers. It stores all your data in an international open standard format and can also read and write files from other common office software packages. It can be downloaded and used completely free of charge for any purpose.

Online Classes for everything from Photography to Music.

This is a Subscription based service for all Adobe products. They offer a "Photographer Bundle" that includes Photoshop and Lightroom for a reasonable monthly fee. They also offer a free trial.

A fun and basic photo editor with effects and graphics. This service is free, but can be upgraded for a small monthly fee to use the premium features. 

Pixlr has similar functions to photoshop elements. It's a web based program that is also free.