[richlevy]

The Old Time Radio Archive has free downloads of old radio shows http://www.archive.org/details/oldtimeradio.

BTW, it isn't all 'radio plays'.

http://www.archive.org/details/TheLesPaulShow

Also

http://www.radiolovers.com/ - More episodes of each show than Old Time Radio.

BTW, if you listen to the first episode of Buck Rogers, you can follow along on the script here:

http://www.genericradio.com/show.php...04fdd014a48482

HUER:
Hardly. The scientific research that led up to the development of this machine was started way back in the twentieth century.
WILMA:
Why, I always thought that the people back in the twentieth century weren't much better than savages! And what they knew about scientific things--
HUER:
Ohh, no, not at all, Wilma! You owe a great deal to the scientists of those days. Were it not for the great groundwork laid by men like Einstein, Fitzgerald, Compton, Milliken and the rest, why we'd be without a great many of the things we have today.
WILMA:
They never really got anywhere with rocketship development, or anything like that though, did they?
HUER:
Well...successful rocket flight depends on two things that have been brought into existence only recently.
WILMA:
One of them must be Inertron.
HUER:
Yes. Inertron. The material that defies gravity and makes it possible to lift a big spaceship off the earth and away from it's terrific gravitational pull, without too much wasted power.
WILMA:
And what's the other?
HUER:
Impervium. The only metal capable of withstanding the high temperature of rocket blast for any length of time.

Wow. Inerton and Impervium. Someone call NASA, quick.