I'm trying to figure out what the population of one of my fantasy worlds looks like. The people don't age and are resistant to some diseases, but aren't immortal in the strictest sense. Their society is pre-industrial, but well-developed and structured. Making it harder to figure is their habit of using others for the hardest, poorest-paying work--most of them aren't going to die of malnutrition because they're on top, basically.
I think I can use statistics from somewhere at least as a starting point.
Edit: General information is always helpful, but I'm really looking for a comprehensive list that breaks it down into numbers by age (you know, like 25% of women died before 40 during childbirth, 10% died from infectious disease, blah blah). If you know of any websites or any books that I could check out from the library, I'd be so grateful. Little pieces of info that I can piece together into a larger picture are also good.