Font Management in Linux, Part 1 - page 3
Linux is lacking in good font managers. KDE's font installer is decent; it finds and displays the fonts on your system that Fontconfig knows about, and installs and removes fonts. It also displays the font type, and you can print a catalogue of all fonts or selected fonts. Use Ctrl+left-click to select non-contiguous fonts, and Shift+left-click to select a batch of contiguous fonts. Each font takes up two lines, so you can cram a lot onto a single page. On ordinary KDE you'll find the font installer in
kcontrol. Kubuntu puts it in System Settings -> Appearance.
Gnome users can go into Nautilus, navigate to the folders that hold TrueType fonts, and click on individual fonts to generate a preview. But it won't work for other font formats. OpenOffice.org Writer and KWord both have nice font previewers, so at least you can quickly see what they look like.