Lookybook and Big Universe have recently been featured on a few other education blogs. Both allow you to read commercially published children's books online for free. Both allow you to position your switch over the "turn page" button to create single switch access.
However, Big Universe, seems to me to be a little ad heavy and some of the books took forever to load, yet it offers a feature to create your own online books.
Maybe next there will be cell phone picture books for us?
