This is an ELPA repository

To use add it to your list of ELPA repositories in your .emacs file:

    (setq package-archives '(("ELPA" . "http://tromey.com/elpa/") 
                             ("gnu"  . "http://elpa.gnu.org/packages/")
                             ("SC"   . "http://joseito.republika.pl/sunrise-commander/")))

You need a fairly recent version of Emacs with support for multiple ELPA repositories for this to work correctly. If you're using Emacs 23 or older you may do this instead:

Unfortunately the version of package.el you obtain by following the procedure described at http://tromey.com/elpa/install.html is older than the one distributed with the latest Emacs sources, and it does not allow to use more than one repository at a time (by default the one at http://tromey.com/elpa/). It doesn't even define the package-archives variable. What you can do instead is the following:

1. Close (C-x k) any *Packages* buffer you may have open (just in case),
2. press S-M-: (or Alt-Shift-: if you prefer),
3. type in the following (parentheses are important):

          (setq package-archive-base "http://joseito.republika.pl/sunrise-commander/")

   and press Return,
4. do M-x package-list-packages, as usual — you should see now the contents of the Sunrise Commander ELPA repository,
5. install the packages you're interested in,
6. Press again S-M-: and type in:

          (setq package-archive-base "http://tromey.com/elpa/")

   and press Return to restore the variable to its original value.

Or you can simply download Sunrise and any extensions you want to use and install them manually with M-x package-install-file.