Raphaël Hertzog, an upstanding French Debian developer, has just finished writing a book about Debian, that hit the shelves yesterday. That book covers many aspects about Debian, from the way the project works to the installation process, migration from other OSes, setup and so on. As a proofreader having spent quite some time over the last few months reading it again and again, I can tell you it's Good Stuff. It's in French though, so we'd probably call it « c'est que du bon ».
Read it, buy it, recommend it to your friends. More info, table of contents, cover, one full chapter, background images, order links, etc. are available at this page.