You do not need Final Draft to write your first screenplay. There’s no reason to spend the money unless and until you have a real need for something like Final Draft. Does it make writing and formatting a screenplay easier? Absolutely. Is it expensive and unnecessary to writing your first script? Also, absolutely.
Writers might try to tell you that you must use screenwriting software. Not exactly. What you must be able to create is a standard format script in Adobe’s Portable Document Format (PDF) for uploading to registry databases and sharing with other writers.
The reality is, plenty of great scripts were written on typewriters, and manual typewriters at that! I’ve written most of my scripts on yellow legal pads before typing the drafts into whatever software was at hand. I prefer Literature and Latte’s Scrivener for OS X as my primary planning and drafting tool, but I’ve used text editors and Word when those were my available options.
My choice of writing tools depends on my need to share files with other people. If you have colleagues using Final Draft or Movie Magic Screenwriter (or any other writing application) it is always easier to use the same tool collaborators are using.
If you do sell a script or work on a production, the standards are Final Draft and Screenwriter. There’s simply no way to avoid using one of these tools, or both of them, during a professional screenwriting career. Some smaller production companies now use Celtx, and even fewer use Adobe Story, but if you earn a living writing screenplays you’ll use the two big names in our industry.
I hope that every member of Carnegie Screenwriters, and aspiring screenwriter, ends up needing Final Draft or Screenwriter.