In his words, this is why Ken Lavine started this cool blog site:
"I’ve started this blog because I’m bitter, bitter that so many aspiring writers waste their time and mine by writing substandard work. Probably at least 75% of what I read is amateurishly written, by people who appear to have little or now understanding of the craft. I’m tired of seeing the same mistakes of writing the same notes and the time has come to do something about it."
His blog posts are worth the read if you want to make it past Hollywood script readers like him to get a foot in the door. He should know as he worked for major studios and has quite the experience.
Scriptshadow is another great site which is mostly about reviewing screenplays. You can send them your screenplay's; if it peeks their interest it will get read and reviewed and perhaps even published on their site. There are also in depth reviews of produced screenplays plus very valuable insights and a lot of tips on screenplay writing. What's cool is the concept artist section in which you can hire two artists to create a movie poster for your film to go along with your pitch or query, awesome idea.
Script is a divison of The Writers Store and focuses on screenplay writing. The Writers Store is aimed not only at screenplay writers, but also towards filmmakers. It's another great resource when looking for anything related to screenplay writing.
The Writers Store is the go to store regarding screenwriting software, books and supplies. It also offers lots of other things like courses, videos, screenplay coverage services, etc. The Writers Store has been around for a long time and is a great for screenwriters.
Creative Screenwriting was crowned “The best magazine for screenplay writers” by the Los Angeles Times, it is a great resource for screenplay writers. It has plenty of useful and informative articles; there is also a store attached.
Another great resource for screenplay writers. There are articles, introduction to screenplay writing tips, a networking section, reviews, etc.
A site created by Ted Elliott and Terry Rossio, an amazing screenplay writing duo who wrote the Pirates of the Caribbean trilogy, Shrek and The Legend of Zorro just to name a few. This site is a gem as it gives screenplay writers tips on everything screenplay related, from an experienced and thorough perspective, from two of Hollywood's most established and successful writers. It also has forums and other useful stuff.
Michael Hauge is a successful coach, lecturer and author with great insights regarding scriptwriting and its business. He has written several great books on screenplay writing and on his homepage he shares lots of free articles about screenplay writing.
John August is another great scriptwriter with a handful of movie hits to his credit; he offers great insight into the screenplay writing world. There is tons of information and podcasts being offered so check him out.
Whatascript has simple but important screenplay rules on characters, structure, format and dialogue and they are all well explained. It is a small site and doesn't feature tons of content but still worth to checking out.
Screenplayology was created to establish screenplay writing as an academic discipline by itself. It is about reading and studying screenplays. It is a great site to support screenplay writing as a literary recognized discipline. It also features some great blog posts and resources.
Corey Mandell’s Blog posts are a treasure trove of information on common scriptwriting topics. He is an award-winning scriptwriter and teacher who wrote projects for the big league in Hollywood.
Another blog worth checking out is this one from Eric Borg, award winning scriptwriter and teacher. His unusual blog posts, although tackling common issues, provide a different angle on scriptwriting.