Where did the land of nod come from in the bible?

in genesis book 4 cain kills abel. he then goes east to the land of nod where he finds a wife and has a son. now up till him killing abel there is adam, eve and their two sons, 4 people. cain kills abel. 3 people. where did the land of nod come from and where did the wife come from. this is direct from genesis and i would just like an answer. and before any one says otherwise, i have read the bible. actually have it in front of me right now so please dont attack me by saying i need to read it. i would like a clear concise answer that doesnt include me just taking it on faith. thank you