Check out finaldraft.com its a really great peice of software that (when inputed correctly) has alot of useful features . Like has Text to Speech (it reads back your script.. a few different voices too) and a lot of production features. But besides that ... sit down.. away from a TV.. and WRITE!!
Then, whether you think you've got something worth writing or not, just write. I have a tendency to want to have everything thought out before I write it down, but every time I just start writing, it turns out better than I expected.
the book "Story" was helpful by me. By Robert Mckee. He's the guy that's made fun of in Adaptation. His book is actually very concise and helpful for writers who are starting out.