http://www.oreilly.com/catalog/debian/chapter/book/
a really good looking debian reference book, that. a couple of years out of date, a lot of the sections are still most relevant.
it connects together a lot of isolated patches of knowledge in my head, i find the best way (for me) to use this book is to take notes while i read the online version. i thought i would print it, but the notes way, i pay more attention and i end up with all the relevant information on a fraction of the paper.

