Ron Downey of the Aviation Archives blog has posted a full Douglas DC-9 FCOM (Flight Crew Operating Manual) which is available as a free download. This is the read deal!
If you are looking for a real DC-9 to enhance your experience flying the Coolsky DC-9 Classic, you definitely need to get over to Ron's blog and get this manual.
Ron's blog is full of manuals for a range of vintage aircraft. I recommend you browse Ron's blog to find even more goodies you might like.