Evidence for God from Science

In Gen 4:15 Cain went to the land of Nod, east of Eden and in Gen 4:16 his wife was mentioned. Please excuse my ignorance of the Bible's timeline, but out of curiosity, where did Cain's wife come from, were there any people in the land of Nod and, if so, where did they come from?

My understanding from reading the Bible is that "Man Kind" was created before Adam, and that Adam was made for the specific purpose of Eden. And then there was Eve, and you know how that went from there. It makes more sense to me than other explanations, seeing as how it properly follows the flow of time, or to put simply, doesn't contradict the book's own chronology. So in other words, he wasn't related to her. When it says in the King James that Cain "knew" her, it's the time's English for "to procreate with". English is really that much different today from how it was back then. King James is still a decent translation, though, if you can grasp the confusing lingo of the day. But I digress.

The more common idea is that everyone committed incest back then. I can't help but to think of this as becoming so popular because of how many people, at least that I've met and heard of, married their immediate family members. Now that's not to say it's not possible for this to be the case, but that's quite a stretch when it comes to my sensibilities.

Whatever you reason about it, though, don't believe it just because everyone else does. If everyone believed trees grew from the sky, and not the ground, that wouldn't make it true. I think if it bothers you that much, you should read a bible, and draw your own conclusions from it, rather than measuring your own conclusions from those of others. Afterward, when you have a good idea of what you've read, it's much less confusing when you discuss your findings with others.