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These sites cost money, but in return allow network executives to peruse your scripts. Usually you pay to get a rating, and high-rank scripts will shoot to the top of the lists. However, many of these sites are unreliable, so be sure to look them up online to find reviews, testimonials, and successes. Look up any "success stories" from the site on IMDB to check their reliability. Accepting unsolicited submissions without a mediator puts companies at risk of being accused of stealing. Getting electronic proof of review by companies is a unique benefit that the Internet provides in today's television development arena. Go online and find phone numbers, emails, submission ideas for companies that are making shows similar to yours. Get in touch however you can, talking to them about opportunities to meet and discuss your ideas. You don't to be needy, just willing to put in some effort to sell your script.  You would never pitch a cheesy monster movie to NBC, you'd send it to SyFy. You wouldn't send a Historical Drama to Greg Danial's (The Office) production company. Think about what the studio is already making to pitch to the right people.  Look into studio fellowship programs. These are paid 6-8 week programs that allow you to hone your ideas at the studio. They are, however, incredibly competitive. Meeting people is still the best way to sell any idea or show. Grab coffee with friends, join an improv group, and take jobs on movie sets. Even if one person isn't able to make your idea a reality, they may know someone who could help.  When possible, work on film and TV sets as a production assistant or intern -- anything to get your foot in the door. While not strictly necessary, selling your idea to Hollywood is easiest if you're in Hollywood. If you're serious, it's time to move to LA. A lot of TV is also produced, however, in NYC. You need to knock the executives out once they give you a chance to speak. Pitching is an art form, but it is more of a sales pitch than a script. Your goal is simply to get people excited about the show, to put the image of the show in the executives' minds so they can envision the final product. To do that, talk about:   The Hook: Return to the "what if" of your show. Why is it original, compelling, and worth watching?   The Audience: Who is this show geared towards? How does it fit with the network's current audience.  The "Trailer:" If you were selling this show in a commercial, what parts would you highlight? What are the "clips" that flesh out the world of the show. Why does your show fit their audience? How does it complement their other shows? Why do they need your show? Don't just talk about how awesome you or your show is, talk about why it is a good decision for them to buy it. You must know what types of shows the network produces, and who its audience is, to capture its attention. Your pitch should be no more than 12-15 minutes, and the shorter the better. Give the executives the idea of the show, hook them into the premise, and let them know why it is a good fit for their network. Then say thanks and answer any questions.  You must practice your pitch ahead of time, multiple times. It needs to be as well prepared as your script and treatment. It can help to have multiple other ideas on hand too, even if they don't have a treatment. They may love you and your idea, but not have room in the schedule for that specific show.
Add your material to a searchable online industry database. Create a list of appropriate companies that might like your idea and approach them online. Network with everyone you can. Know that you'll need an effective pitch to sell your idea once you're in the door. Remember to be a salesperson, not a writer. Pitch quickly and energetically.