[CentOS] CentOS Firewall configuration

Hello,
    When i did the basic CentOS install i selected incoming ssh, ftp, www, 
and smtp in the configuration dialog. Now my needs have changed and i'd like 
to add to those rules with samba, this box runs it, and bacula the client. I 
was wondering a howto on what to put, i know the ports i need, or a web 
configuration util?
Thanks.
Dave.