Every action appears on the appropriate NA list, and all NA lists are kept together. (In a notebook, in my case.) Anything else pretty much guarantees that stuff will fall through the cracks.
Project-specific reading material is filed with other project support materials and given an NA in the appropriate context. General reading material goes in a "to be read" file, which I purge every few months.
My approach to reading is that it's impossible to read everything, so I don't try. I read everything project-related (which is quite a lot), and a sample of general stuff, and let the rest go.