i dont think the specified age or target audience is important when relating to AOS.... as someone else said, you can nearly use anything.
i prefer to use stuff that im interested in as my related material. thats why i usually use music... in the case of imaginative journey i used "One Mic" by Nas... its pretty good, and shows imaginative journey pretty well... i also used everyone's favourite picture book - "Where the Wild Things Are" (remember that?)
those were for my 1/2 yearlies, and i did pretty well