The great thing about KDE is the ability to customize just about every aspect of the desktop environment. Wallpapers, themes, widgets, colour schemes, splash screens and more, the options for customization are endless.
KDE-Look.org is the number one location to find customized settings for your KDE desktop. Some of the applications within KDE even allow you to connect directly to KDE-Look and download a new configuration or image.
For further information concerning Desktop Customization, please review the System Settings Documentation.