Logically speaking I don't really know where to start wth this. I'm not saying there is or isn't a God, only that this argument isn't helpful to that answer.

This issue is that we got here because we're the way we are. If we weren't wired this way, we wouldn't be here.

Or to put it another way, you're assuming the inevitability of our existence then reverse engineering the rest.

I remember an interview with some intelligent design guys. They kept talking about how intricate nature is and how well it fits together, and that could only be true if there were an intelligent designer.

Except that argument doesn't make sense. Evolution would imply everything fits together, too, because otherwise the ecosystem wouldn't function. Things fit together because they have to in order for there to be a natural world. That which doesn't fit gets weeded out (or the system collapses and everything dies).

I remember an old argment about how some god must have created life because the probability of spontaneous generation of life is so low. But again, that's assuming that we were definitely going to exist. Evolution says the odds are low but we got lucky and here we are. The other N-1 times it didn't work so it didn't produce anybody to sit around and wonder about it.

There's no way to prove God exists until he/she/it shows up and passes out a business card. Attempts to do so are doomed to failure.

Of course, the atheists are screwed too, because they can't prove the non-existence of God, either. Just because he hasn't show up doesn't mean he won't.