You can also find them in the movie. If I recall correctly, they were used by someone on the orbital Hilton and by the astronauts on the discovery.

Samsung recently used the movie as evidence of prior art against apple [1].

[1]: http://appadvice.com/appnn/2011/08/samsung-uses-2010-a-space...

2001. They are seen aboard the Discovery, but they don't show touch interfaces (unless George Lucas somehow got hold of the rights and disfigured a masterpiece).

I believe it was fairly late in the book, but I'll look up the exact line when I get home this evening.