You can buy the book as a hard copy or as an ebook. If you find the ebook offered online for free it's a pirate site. The book is never legitimately free. Many of these pirate sites look legitimate but they are not, and many have malicious software. Lots of any honest people have been fooled by this.
How to buy
You can buy the book in paperback or ebook. Now I have to apologise - big time. The problem is that there are two editions of the book, both the same. This is because the book has two publishers, one who sells to N. America, the other that sells to the rest of the world. To add to the confusion, the ebook is available on N.America Amazon but not Amazon elsewhere. Elsewhere it is available via Google books.
Not surprisingly, all of this confuses the Amazon robot... The Amazon robot (apart from Amazon Germany) often gets very confused when people who are not in North America try to buy the hard copy and the ebook. Amazon UK for example may refuse to sell to you. Everything I and the publishers do to try to sort this out with Amazon seem to fail. That is, apart from Amazon Germany, which will sell you the hard copy but not the ebook (since that's available only on Google) . I know – it drives me crazy too. Here are two reliable online sites.
21st Century Screenplay
The 21st-Century Screenplay is the long-awaited, much-expanded successor the author's internationally acclaimed book Screenwriting Updated. Many books in one, it offers a comprehensive, highly practical manual of screenwriting from the classic to the avante-garde, from The African Queen and Tootsie to 21 Grams, Pulp Fiction, Memento and Eternal Sunshine of the Spotless Mind.Whether you want to write short films, feature films, screenplay adaptations, genre films, ensemble films, genre films, ensemble films, blockbuster or art house movies or parallel narrative, this book takes you all the way from the choosing the brilliant idea to plotting, writing and rewriting.
Featuring a range of insider survival tips on time-effective writing, creativity under pressure and rising to the challenge of international competition, The 21st-Century Screenplay is essential reading for newcomer and veteran alike.
Praise for 21st Century Screenplay
‘A brilliant book. Linda Aronson is one of the great and important voices on screenwriting.’
Dr Linda Seger, author of Making a Good Script Great
"As a screenwriting teacher at New York University I recommend a broad spectrum of textbooks to my students. I tend to the view that most of these books offer something of value and each of them is essentially as good as the person who reads them. In the case of Linda Aronson’s work I make an exception. The 21st-Century Screenplay addresses areas not covered by others. The book provides the services of a personal script editor, dramaturg or even co-writer. It functions as a manual as well as a road map"
Paul Thompson, New York University
‘A VERY WONDERFUL book. I love the strategies for plumbing the unconscious story mind. There’s no other book that gives such an in-depth analysis of the “bone structure” for all these various kinds of narratives.’
Robin Swicord, Little Women, The Jane Austen Book Club, Memoirs of a Geisha
'It’s a huge achievement, an incredibly comprehensive analysis of what the screenwriter does, of what can go right and what can go wrong and how to fix it when it does. I highly recommend it.’
Andrew Bovell, Lantana, Blessed, Edge of Darkness