Scribus
The Official Manual

Here it is, my book. Strictly speaking, not just my book, but the collaborative book I blogged about, I don't know when.

It's been an interesting experience, and no one's going to get rich from it. In fact, I'm donating any money I might have made to the software project that wrote the software that the book is about.

So, if you're interested desktop publishing, you might check out Scribus, and the book.