Where Are All The Half-Evolved Dinosaurs?

I don't profess to have a very proper understanding of the mechanics of the Darwinist theory of evolution, so I'm always a little wary to blindly refute it based on the little knowledge I have, and so I keep an inquisitive mindset into what exactly is valid and invalid about this theory that so many people take as absolute fact.

Here's an article that asks a simple question: Where are the fossil records of all the not-fully formed predecessors to the fully formed species that we have dug up and that we see living today?