The Official Ubuntu Book is out in a new edition to match the 7.04 release of the software.
Read it at Techbookreport
As mentioned previously, there are chapters devoted to some of the other Ubuntu 'projects'. For example there is a chapter on Kubuntu, which is a version of the operating system that uses the KDE desktop rather than the default GNOME desktop. There is also a chapter on the Server version, including topics such as setting up RAID storage and the like. While it's good that there's some coverage, the truth is that anyone seriously looking at setting up a Server box would be better off looking at a more technical book than this one.