Gee, this guy's material is everywhere. Which is why it can be hard to find.
But: http://www.runtimedna.com/Sixus1/?sort=&page=4 has the heart of the Cthulhu mythos (remember, five inventory pages at least at that location), more (and different) here: http://www.contentparadise.com/searchimageviewdetail.aspx?bucket=4&searchText=Sixus1Media and the new material he is working on.
Been a while since I visited. My rendering days are probably behind me, but if you have an interest, not a bad place to start looking. Not to mention, he had hundreds of lower resolution models and material he never released.
And pages of freebies at http://www.sharecg.com/pf/full_uploads.php?pf_user_name=Sixus1Media