Librarian of Congress, Dr. James H. Billington, says,
Her appointment to the position has garnered, if not controversy, then at least curiosity. Poetasters and critics alike acknowledge that while Ryan's poetry has similarities to that of Emily Dickinson or Marianne Moore, she does not write in what is considered the current style of poetry.
At present, SFPL has one Kay Ryan book, Elephant Rocks. We have several more on order that you can start placing holds on. In the meantime, that catch-all Wikipedia has a great selection of her works and criticism available online.