Upon further Googling, I came across http://antiochapologetics.blogspot.com/2009/05/hebrew-new-testament.html, which agrees that Hebrew thought patterns are the basis of much of the non-Pauline NT, but seems to show that the actual documentary evidence so far found indicates that oral traditions may have kept the accounts alive until Greek was used to first write the NT.
I do remember seeing scanned excerpts of Greek manuscripts with just the Tetragrammaton written in some form of Hebrew, including Greek spoofs of the Hebrew Tetragrammaton such as PIPI [that is pi-iota-pi-iota].