Does anyone know where to get a copy of the two-act play Bradbury wrote based on Farenheit 451?

I recommend that you try the Dramatic Publishing Company. Here's a link to their website. Under "Search", simply type in "Ray Bradbury" or "Fahrenheit 451".
http://www.dramaticpublishing.com

It's not on dramatic publishing, does anyone else have any ideas where to get a copy of this play?

Well, I found it on The Dramatic Publishing Company's website. Here's a direct link to the list of Ray's available plays. FAHRENHEIT 451 is on the list...

http://www.dramaticpublishing.com/AuthorBio.php?titlelink=9094

Thanks, Richard, I must have been searching in the wrong place. Martian Chronicles is in there, too. Quite a little treasure trove. Cheers.