Secret Corridors

Allrighty, some of you may have seen my post right below this one, titled something along the lines of the I'm out of BT and still have a question. I've been looking and looking for secret passages and John Howard's journal entries, BUT I CAN'T FIND THEM!! Was the solutions guide just giving me a nice fat red herring when it said that there might be secret corridors and such? I love exploring thigs like that.