This page contains links to software that I use, most is Open Source and available free.
It is by no means a complete list, there are many other good programs available.
You will not find links for Photoshop or other 'non free' software
You will have to 'Google' for those.

Software:
Gimp: http://www.gimp.org  
UFRaw: http://ufraw.sourceforge.net
Raw Therapee: http://www.rawtherapee.com/
Xnview: http://www.xnview.com/
Xnconvert: http://www.xnview.com/en/xnconvert/
Xnview and Xnconvert are not open source but are free for personal and education use.

All are available for Linux, Windows, and Mac OS.

Equipment ( camera reviews etc. )
Digital Camera Review: http://www.dpreview.com/
Digital Camera Resource: http://www.dcresource.com/
Imaging Resource: http://www.imaging-resource.com/

D.T.P. and web software
Bluefish: Web design: http://bluefish.openoffice.nl/
Scribus: Linux D.T.P. http://www.scribus.net/

Linux:
Linux - Wikipedia: http://en.wikipedia.org/wiki/Linux
Ubuntu Linux: http://www.ubuntu.com