If you don't have any screenplay sales under your belt, you're going to have to approach an agent cold. Without being able to say, "Hey, I've sold a script! Sign me.", you have to entice them some other way. There are two ways to get somebody to read your script. You can network and get to know them on a personal level, then ask them to read your script as a favor. Networking, however, can take years to cultivate the kind of relationship where an agent is willing to do you the personal favor of considering your script without it feeling like you're using him. Your other option is to query. Send a letter to agents, asking them to read your script. Since you don't have any sold or produced screenplays under your belt, your letter has to convince them that your script is worthwhile anyway.

In order to maximize your chances of getting a sale or agent, you should submit to production companies as well as agents. An option (or better, a sale) to a production company can often do wonders when it comes to finding an agent. Almost any agent would be happy to take on a client (and take his 10%) that's already done the legwork and found money for his work. When sending query letters to production companies, call ahead of time and make sure you know how to spell the name of the person you're sending it to, and what their exact title is. Screenplays are read and considered by the Development (or Creative) department. Just call the production company (contact info is listed in the Hollywood Creative Directory) and ask the receptionist if they accept new material... and if they do, to whom you should address the letter, and what their title is.

You should NEVER send your script (or a treatment or anything other than the query letter itself) unless the company first asks for it. Legal reasons prevent companies from accepting or even looking at material submitted without their express permission or a pre-existing working relationship. At best, your script (or treatment or whatever) will be returned to you unopened, or thrown away. At worst, you'll be put on the company's blacklist and never allowed to submit anything again. Just send a query letter... if they want to read your script, they'll ask for it.

The best way to optimize your chances of getting an option or a sale is to send it to as many people as possible. Agents, if they like the script, will send it to the production companies they have connections with. Production companies, if they like the script, can pay you for your work, or at least give you the clout to get an agent.

How hard is it?

Hard.

About 100,000 scripts get registered with the WGA each year and these scripts are out there for many years trying to get sold.

Only 5% of all films made each year are spec scripts. That means 95% of all films made are sequels, adaptations of books, remakes, script ideas from studios or producers, materials from other mediums (like comics, graphic novels, newspaper stories, you name it) or scripts pitched from established writers.

But someone is selling those 5%. And it's the people who take their time to write a compelling story, whether serious or scary or funny or thrilling or action-packed AND learn how to get it out there within the system the studios and prodCos have set up that succeed. There are no shortcuts. There are no tricks. There is NOTHING that hasn't been tried a hundred times or more.

Plus that compelling story has to be in flawless format, with no spelling errors. Written in the leanest way possible in real time, showing only what will be ON the screen.

Whether you use the query system or the networking system, or try the contests, all of it takes more time than you would ever think it does. There is NO instant gratification in screenwriting. NONE. The average time from option to principal photography for a script is about 8 years.

If you expect the script you are writing today to see the screen, look about 8 years into the future for it to happen after you option it. Some have taken longer. "Runaway Bride" and "Witness" (which won the Oscar for screenwriting) took ten years each for example. And some take shorter time, 3 to 4 years. But it's always YEARS. Not weeks or months.

If you are choosing to do this, then you have to be patient, hard working, and determined. You have to LOVE rejection because you'll get a LOT of it. You have to be open minded to change. You have to be willing to sell your script and let it go for someone else to rewrite. You have to be willing to hand your vision over to others who will do ANYTHING they want with it. You can't demand to direct it, or act in it, or cast it, or even be on the set if they film it.

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The aim of an argument or discussion should not be victory, but progress.
Joseph Joubert, essayist (1754-1824)