I want to implement a plugin system into my application. And I was wondering how can I go about doing it? Is there any good tutorials for KDE4? And would I need to do anything special to have like a menu to open up a file dialog and load the plugin manually?

Hey, what should these plugins do? For UI plugins, kpart is often used: http://techbase.kde.org/Development/Tutorials/Using_KParts

If it should be more general, have a look at the kate plugin system. This file is for the manager to load the plugins:
http://websvn.kde.org/trunk/KDE/kdesdk/kate/app/katepluginmanager.cpp?revision=752361&view=markup

And here is a directory containing plugins. There is also a skeleton plugin for the most basic implementation
http://websvn.kde.org/trunk/KDE/kdesdk/kate/plugins/

cheers, m

Well it will be to allow cosmetic changes, bots, etc in C++, or in Python, Ruby, or KJScript via Kross.