Genesis Books 1-5

I found it both interesting and surprising that we are given a pretty precise location of where Eden supposedly was. Why is it that no one has found it yet? I am sure people have gone on expeditions, it is just surprising that nothing has turned up. Additionally, I find it ridiculous that all the men mentioned lived until they were on average 900 years old. Scientifically, and I know we're supposed to analyze and get out of our scientific thoughts, people lived much shorter lives the farther you go back in history. Maybe it is a metaphor to tell us that when humanity was good, and there was peace in the world, people lived longer or something of the sort.
In terms of how it is written, I personally believe that it is too repetitive. I have never read the Bible before, and so far I like it.