http://www.screenplay.com/products/mms/index.htm
The above link will give you a page for the Movie Magic Screenwriter, a
great program to use. I love it, and once you get the hang of it, you can write great, professional scripts.
The above link leads you to two options.
a) A demo (Under the "buy" option"). This is what I have. The demo allows you to print one full-length script- but only one. After that, you must buy the program. There is no time limit, you just have to choose only one of your works to be able to print. You CAN write as many scripts as you want- just know you are only allowed one in hard copy.
b) The full version, available to purchase. However, if you're like me, a kid with a small income and many things to buy, the $224 price is a little much.
I suggest going for the demo. I promise you you'll like it.
And good luck!