The rpm packaging tool that is used by the Red Hat, SuSe, Caldera and Mandrake distributions has a switch (-qd) that will list the documentation files that come with a package.
For example, the following command will list the documentation that comes as part of the bash package:
[~/]> rpm -qd bash /usr/doc/bash-1.14.7/NEWS /usr/doc/bash-1.14.7/README /usr/doc/bash-1.14.7/RELEASE /usr/info/bash.info.gz /usr/man/man1/bash.1 /usr/man/man1/sh.1
As far as I know, the Debian packaging tool (dpkg) doesn't have a similar option, but you can use the -L switch to list the contents of the package, which will show you all of the files, including the documentation:
[~/]> dpkg -L bash
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