For those of you who are creative and looking for some professional, classic fonts... please take a look at Font Deals new 2011 Summer Font Bundle. For only $49 you get 15 high quality font families that look and work GREAT in Ubuntu. In all, you get 29 fonts!
These are EASY to install in Ubuntu. Just double click a font in Nautilus file browser and the font will open up in "font viewer". You can see the font style and then simply click the
"install font" button.