In enterprise manger, open the server, then open the database. Above tables you should see diagrams. Select diagrams, right click and click new diagram. When the blank diagram opens a wizzard should open. Check "Add related tables automatically" And change the number of levels to what ever you need. I usually just set it to 99 to make sure that I get everything. Then click through the rest of the wizzard.
Yes visio has a function to reverse engineer a database from it's tables, views and procedures. So you shouldn't have to do much by hand.
Denny
--Anything is possible. All it takes is a little research. (Me)