A Guide to Scriptwriting - Written by Routledge, this guide covers the finer points of character creation and world-building and details how to write a script in eight steps.
Writers Guild Foundation Resource Center - Vetted by the Writers Guild, this site provides guidance on writing a personal statement, where to find scripts online, and more.
Writer Resources: Script Standards - The Black List provides script formatting standards for film, television, and theater to ensure that scripts can be compared on relatively even terms.
Screenwriting Guide - From Loyola Marymount University, this guide to screenwriting provides common vocabulary terms and definitions for developing the structure, format, and elements of your story.
Internet Movie Script Database - While this database of scripts for feature films may look old, it is the premier resource in the field and features dozens of downloadable scripts.
Analyzing a Script - From the Association of American Cinematographers, this article walks readers through best practices for assessing a script as well as tips from cinematographers for analyzing scripts.
Film Analysis - Written by UNC Chapel Hill, this handout introduces film analysis and offers strategies and resources for approaching the topic.
Podcasts
Scriptnotes - This weekly podcast on screenwriting from John August and Craig Mazin makes the 20 most recent episodes freely available; the back catalog is restricted to subscribers.
Bulletproof Screenwriting - Focusing on all things screenwriting, this podcast interviews award-winning writers like Jordan Peele.
Draft-Zero Podcast - Released monthly, hosts Stuart Willis and Chad Fisher discuss various writing devices, why they're necessary, and how to employ them.
Script Apart - Hosted by a journalist, this podcast looks at scripts behind popular movies and changes that were made - or not made - during production.
Videos
Interviews: An Oral History of Television - Although not exclusive to screenplays or scripts, this resource provides videos of interviews with important figures in the world of film and television.