This post is related to deb packages.
Files from an installed deb package can be listed with
dpkg -L pacakgename
The inverse can be done with apt-file:
apt-file search /path/to/some/file
Config files are a little trickier.. can't remember exactly how to get a list of a packages config files. However, you should always read the documentation in:
especially the README.Debian file. This will usually give information about configuring your installation of the package.