User blog comment:Star runner/Codex Astartes/@comment-2045915-20100729192708

No, there is no actual Codex Astartes, it is a plot device sprinkled throughout the various Space Marines Codexes. Our wiki has most of the known excerpts. Sorry, you can buy the various Space Marine Codexes if you want the original texts, but for now, the wiki is pretty complete on this subject.