I've finished exploring the caves with the trolls and I have the archaeologists' book. Now I can't find Lendon or Jax! Only the automaton "archaeologists" are around the camp (i.e., the fenced-in area). Where are they?? I spent 15 minutes running around looking for them. Did I forget where they were, or is there a glitch in the game?

You mini-map should have the Archeologist barracks marked on it. Jax will be right next to the front door of this barracks. Lenton is inside, in the back. It's always worked fine for me.

As for going inside the barracks, I can't get in, "the door is barred from the other side." And Jax isn't there.. strange! I wonder if it's possible that I took too long to do the quest??

I think the barracks have 2 doors, so look for the other one.

I did. Both doors are barred from the inside. Jax and Lorman or whatever he's called are nowhere to be found. Only the normal "archaeologists." Is it possible that I took too long in my quest? When I first encountered Jax, I was low level and I refused his quest, and he said something like, "If you change your mind, come back." So I came back and did it some time later, but now I can't find him. I am highly peeved because it took me a very long time to get his darn book.

What should I do?

The only thing I can think of: Start a savegame from just before you pick up the book (hopefully you have one)and go to the house without picking up the book and try to get the quest. Good luck!