Polish institutions links: 
Supreme Court
Supreme Administrative Court
Constitutional Tribunal
National School of Judiciary and Public Prosecution
Ministry of Justice
Human Rights Defender (ombudsman)

European and international institutions links
Court of Justice of the European Union
European Court of Human Rights
European Network of Councils for the Judiciary (ENCJ)
Consultative Council of European Judges (CCJE)
European Judicial Training Network (EJTN)

Links to guidelines and handbooks
"Communication and image of courts" - Collection of good practices, for common courts (in English and Polish)
"Court ABC - handbook for journalists" (in Polish)