Hello everyone. Its nice to be on this forums.

I had few C++ classes before, basic into to C++ and class which touched on object oriented programming, trees, arrays.. etc. But I never had chance to make that programming somewhat meaningful (I was just doing different, in-class assignments for programming from command line).

I would like to start developing something for KDE. (As a way of practice. Maybe start from some tutorials and start to learn basic things).

I picked KDE since how I understand KDE mostly use C++ while Gnome and GTK use C. I also favor KDE more than Gnome, just had difficulty adapting to earlier versions of KDE 4.

Can someone help me with this? Maybe direct me somewhere? or give me some ideas, recommendation from where to start?

Does anyone know where I can find tutorials on how to start developing something? (something simple to start with). or maybe someone can recommend me some good books on this subject?

And what kind of IDE can I use?
I heard of Qt Creator and also KDevelop..
Can someone recommend me something?

You may wish to look at the Qt tutorial: http://doc.trolltech.com/4.3/tutorial.html
You may also wish to check the KDE Tutorial's located on Techbase: http://techbase.kde.org/Development/Tutorials

Can someone help me with this? Maybe direct me somewhere? or give me some ideas, recommendation from where to start?

- One recommandation: find a bug that affects you, or feature that YOU miss, troubleshoot it, and fix it. That's definitely the most motivating way I found to start coding. You can find plenty of at http://bugs.kde.org/

- Do not hesitate to contact the maintainer on IRC or by e-mail. They are always happy to help you contribute.

- Read dev-mailing-lists, and join on IRC to see how things work in KDE: you will learn how to submit code, ask for input and so on.. (I mean technically but also, how to make it accepted by people: yes, there are some kind of implicit rules to learn in an open source community).

Does anyone know where I can find tutorials on how to start developing something? (something simple to start with). or maybe someone can recommend me some good books on this subject?

I'd say http://techbase.kde.org + the Qt tutorials: they are excellent to familiarize with Qt.

And what kind of IDE can I use?
I heard of Qt Creator and also KDevelop..
Can someone recommend me something?

Both are fine. Until recently it was easier to handle KDE projects in KDevelop, but I think now qt creator handles natively the cmake projects (Please someone correct me if i'm wrong here).

Good luck!