This is a quick tip, howto find, query and list all available packages from a specific Yum repository/repositories on Fedora, CentOS, Red Hat (RHEL). This trick does not show the already installed packages from selected repository.

List All Repositories and Check Repository ID’s

$ yum repolist
Loaded plugins: dellsysidplugin2, refresh-packagekit
repo id                                                      repo name                                                                        status         
adobe-linux-i386                                             Adobe Systems Incorporated                                                       enabled:     17
fedora                                                       Fedora 12 - i386                                                                 enabled: 15,366
google                                                       Google - i386                                                                    enabled:      4
livna                                               for 12 - i386                                                      enabled:      3
rpmfusion-free                                               RPM Fusion for Fedora 12 - Free                                                  enabled:    383
rpmfusion-free-updates                                       RPM Fusion for Fedora 12 - Free - Updates                                        enabled:    551
rpmfusion-nonfree                                            RPM Fusion for Fedora 12 - Nonfree                                               enabled:    124
rpmfusion-nonfree-updates                                    RPM Fusion for Fedora 12 - Nonfree - Updates                                     enabled:    228
updates                                                      Fedora 12 - i386 - Updates                                                       enabled:  4,587
repolist: 21,263

Query Available Packages From Selected YUM Repository

Disable all repositories and then enable just selected repo.

$ yum --disablerepo="*" --enablerepo="google" list available
Loaded plugins: dellsysidplugin2, refresh-packagekit
Available Packages
google-chrome-beta.i386                                                          5.0.307.9-39052                                                       google
google-chrome-unstable.i386                                                      5.0.322.2-38810                                                       google
google-desktop-linux.i386                                                        1.2.0-0088                                                            google