Great post Fred, but let's not forget season 5's "Fifty-One"(ep.4). Where jesse gives Walt a watch for his birthday. And at the end of the ep, Walt places it on the nightstand atop said book. With the second hand ticking like a timebomb to close out the ep....
Now fast forward again to season 5. "Leaves of Grass" pops up in eps 3, 4, and 8 before Hank finds it. Walt just had it laying around the house.
Fred.