Raillery: the funny underbelly of computer games
Yes, you need a version of the CoC book to run. Delta Green is more of a "Campaign Setting" for CoC.
Can you run it with the D20 CoC?
http://www.kickstarter.com/projects/arcdream/through-a-glass-darkly-a-new-delta-green-novel
Ross! They stole your Eclipse Phase game name!