Question: I just bought a house and the former owner said the rock on
the house was full of rattlesnake fossils. I'm attaching some photos of
the rock. I've been told that these fossils are not from a rattlesnake
but from something else?

Answer: We have decided these are sea shells called Trilobites as seen
at:
http://images.google.com/images?q=Trilobites&hl=en&btnG=Google+Search

I think the word you're looking for is gastropod (or maybe they said Turritella, which is a variety of gastropod). Basically, these are fossil snail shells from the Cretaceous Period (163 to 65 million years in age - during dinosaur times), and are very common in the limestones of this region.