Hello,
I am interested in setting up a website that will allow the a person to broadcast a radio show each night live.

Could you give me some idea as to how to do this?

What will the server need, what kind of software to use, and what kind of script I will need?

Basically, my brother wants to "host" a live talk show each evening about sports, through the internet on his website.

So all input would be greatly appreciated.
Thanks.

Shoutcast (http://www.shoutcast.com) and winamp are quite good options. If it's just going to be a small talk show with a few listeners he can just set it up on his home computer (if he has a DSL/Cable line with upload speed of 256K, he could support over 10 simultaneous listeners at only 16K (probably good enough for talk)). Then you just link to the stream from the website.

There are other options too. Live365 are quite cheap for small operations, but if you're looking at doing a big show, a dedicated server with Shoutcast installed, or a system from a shoutcast or streaming provider host will work well.