What You Need to Play

The Book

The only book you'll need is Basic Fantasy Role-Playing Game by Chris Gonnerman. The Basic Fantasy Field Guide would be helpful for Game Masters as well. The pdfs for these books can be found here. A print copy can be had for $5.

The Dice

The standard array of dice, you'll need a set or two. These can be found at any Game Store or for really cheap on Amazon. 

The Pencil

Pretty self-explanatory.

Your Imagination

That's it. That's all you need. Have fun!