Fonts are really easy to configure in KDE. Open up the Control Center (with K-Menu->Control Center) and choose Font Installer in System Administrationin the tree view.

There are two kinds of fonts: Personal and Global fonts. Personal fonts are only accessible to your user, whereas global fonts are accessible to everyone. When you open the Font Installer, you're in Personal mode (you can see this in the Location bar). When you click on the Administrator Mode button, and put the root password, you can access global mode, where you can change the fonts for every user on this computer.

For the rest, there is no difference between those two kind of fonts.

There is a list of fonts in the center. Click on a font to see a preview. In the toolbar on the top you have buttons to access the top directory, refresh and change the view.

If you want to, you can organise your fonts in multiple directories, so that you can easily find them later.

To install a font, click on the Add Fonts... button. A file open dialog will appear where you can choose your font.

Alternatively, you can drag fonts from Konqueror to the list. To remove a font, right click on it and choose Delete.

Configuration (anti-aliasing)

kfontinst and kfontview should probably get a mention too, since they don't seem to have any existing docs.