The American Civil Liberties Union (ACLU) "is our nation's guardian of liberty, working daily in courts, legislatures and communities to defend and preserve the individual rights and liberties that the Constitution and laws of the United States guarantee everyone in this country."
This particular page focuses specifically on banned books.
Created by the National Coalition Against Censorship (NCAC), this kit contains a "collection of materials on the topic of censorship in schools for the use of students, educators, and parents everywhere."
The Comic Book Legal Defense Fund (CBLDF) has a free handbook that "that gives you the scoop about what comics are banned, how to report and fight censorship, and how to make a celebration of Banned Books Week in your community!"
"The American Library Association affirms that all libraries are forums for information and ideas, and that the following basic policies should guide their services." Article III specifically focuses on the of censoring materials.
"The National Coalition Against Censorship, an alliance of fifty-two participating organizations, is dedicated to protecting free expression and access to information." This page lists the participating organizations that could offer support.
The National Council of Teachers of English (NCTE) "offers advice, helpful documents, and other support to teachers faced with challenges to texts (e.g. literary works, films and videos, drama productions) or teaching methods used in their classrooms and schools. "
"The Office for Intellectual Freedom (OIF) is charged with implementing ALA policies concerning the concept of intellectual freedom as embodied in the Library Bill of Rights, the Association’s basic policy on free access to libraries and library materials." The OIF is an excellent place for support and resources concerning challenged and bans.