The linking books are inside the rotating domes, PJones. If they are not active, that means that you have not yet gotten power to them. Unfortunately, that means another trip to the fire marble puzzle in the upper gold dome.
After you set the marbles (all but yellow) and lower the plate over the grid (leave it in place), there is a little white button on the wall that you must push. If you placed the marbles correctly, you'll see and hear the power surge (like a mini explosion). Then you should be able to access the linking book in any of the rotating domes. Good luck!
"Nanny Ogg looked under her bed in case there was a man there. Well, you never knew your luck."
-Terry Pratchett, Lords and Ladies