Making a book using docbook

Hi all Docbook gurus (newbies too :) )
I'm about writing a second book & I can't bear word anymore, so
I suggested to my editor to get a docbook XSLT based sheet...
I've got it..So now, I must use Docbook!!!
Like with big documents in LaTeX I guess that it's easier to have small 
files one with its
proper aim...
So I looked into the CVS for the docbook manual , I saw exteensive usage 
of entities & a lot of
files with small sementaic (index,bibligraphy, glossary..)
That's quite what I want but I'd like to be able to have each file 
declare its DTD because
I could be able to use the completion features of my editor...
So any idea welcomed, URL or small example appreciated
Thanks
Jerome

-- 
Auteur cahier du programmeur Java tome 2 - Eyrolles 10/2003
http://www.eyrolles.com/php.informatique/Ouvrages/ouvrage.php3?ouv_ean13=9782212111941