The Pennsylvania Library Association
This is the public library association in PA, formed in 1901. Check out their advocacy webpages with a link called Capwiz. Capwiz is a service provided by the American Library Assn. that allows librarians, parents and other citizens to send a preformatted email to PA and US legislators. PaLA often updates the messages based on pending legislation that libraires need to have passed.
Pennsylvania School Librarians Association
Founded in 1972, PSLA is an independent, incorporated professional organization, organized in 1972, for public and private school librarians and library educators from universities within the Commonwealth that offer library science programs and degrees.