The comment Hitchens makes about mormons is the second of the two videos presented here:
http://freethoughtblogs.com/pharyngula/2011/10/10/hitchens-in-texas/

He talks about Joseph Smith and Smith's wish to be the American Mohammed.

The sharp-witted intro into the subject of mormonism begins at about 2:00 in the second video.

Video of Richard Dawkins presenting the Richard Dawkins Award to Christopher Hitchens:

http://www.youtube.com/watch?v=lp2B0t1SqoU&feature=youtu.be

And here's another source for Hitchens talking about mormons and other subjects. He is seated after having finished his acceptance speech for the Dawkins Award.
http://www.youtube.com/user/janetgoelzer

Just noticed that Hitchens mentioned the "Salamander" episode.
Excerpt below:

As for mormonism, there's so little left to say, but one might as well. I mean look, the salamanders, the underwear, the whole [shebang?].

The real question it raises in my mind is that we don't have many controlled experiments where we can see a religion actually being nailed together. And it's in the classified small ads of the newspapers of upstate New York where you can see the work of a well-known local fraud, convicted felon and conjurer actually doing it. And it's now the fastest growing faith of its kind in the world. This gives us every license to think that the origins of all other religions were equally bemired and bemerded with simple charlatanry and fanaticism. And, I might add, a kind of fanaticism too in that it's probably true to say that it's not a Christian organization. In the straightest and litteral sense intended by your pastor Jeffers (sp?). Almost no one ever points this out except me, Joseph Smith said that he didn't want to be Jesus, but Mohammed ....