Evolution is not a belief system. I do not
believe in evolution, I
understand it. Not only is there sufficient evidence but the evidence is overwhelming. There is comparative anatomy, embryology, DNA, a massive fossil record of transitional fossils. It is not based on assumptions, it's based upon evidence, which there is an abundant amount.
I'm not sure you understand how rock layers work and what fossils are found there.
Here is a helpful link for you:
http://www.prehistoricplanet.com/news/index.php?id=48
The cool thing about fossil discovery is that evolution can accurately predict what they will find and where they will find it.
For example, paleontologist, Neil Shubin was on the team that discovered Tiktaalik (the transition from fish to amphibian). Him and his team predicted how old the fossil would be, where they would find it and what they would expect to find. They took out a geological map and searched on an island in Canada. After 5 years of study, they found Tiktaalik (You can see the fossil in a Chicago museum). They accurately predicted what they'd find and where they'd find it.
I highly recommend the 3 part documentary "Your Inner Fish". It's done by Neil Shubin. It's a very well done and interesting documentary. It should help clear up any misunderstandings you have about the theory of evolution.