I helped someone publish a book a few years ago. A professor at NC State, he needed help with a math book he wanted to write, he was fluent in Xfig and needed a linux machine and help with linux as he knows xfig and latex but nothing else. Later on he had problems with the publisher who requires everything in postscript, but for some reason was having problems with the .ps files we gave them. Apparently Adobe Acrobat Distiller is buggy as hell and if using ghostscript to create the files Distiller pukes on some of them.
I had to go through about 500 pages, page by page, print and read every single ghostscript file with Distiller, and reedit any page distiller couldn't render correctly.
Oh yea, another thing we ran into... just because your OS includes a certain font or you downloaded it for free somewhere, doesn't mean you can use it in a book. That was our fault, but the publisher caught it. They offered us a typesetting service (basically they offered to rerender everything in a commercial font) but it was hugely expensive compared to just giving them the .ps files and having them print and bind them.
I'm using the term "publisher" loosely, basically they were a printing service.