I only know of three distros that use Yum.... and I'm pretty sure you're not using Yellow Dog Linux. Basically, Suse and Fedora ship with no yum repos set up. All they are is a file in /etc/yum.repos.d that tell yum basic stuff...
Code:
[base]
name=Suse Linux - Base Repository
baseurl=http://download.opensuse.org/distribution/SL-10.1/inst-source/suse
#mirrorlist=http://www.personal.uni-jena.de/~p1woro/suse-yum/suse-base.mirrors
enabled=1
gpgcheck=1
gpgkey=http://download.opensuse.org/distribution/SL-$releasever/inst-source/pubring.gpg
This is a simple file called
suse-base.repo and if there's a file called
suse-base.mirrors it will use that as a list of mirrors to try if the base is unavailable. I did a google search for Suse yum repositories and came up with a few good ones. You'll definitely want to add suse-base, suse-extras, and packman. If you're running Fedora, you can get a list of repos from the
Myth-TV on Fedora Howto.
Liquidat's Howto for Yum on Suse 10.1 suse-base.repo (right-click and save in the
/etc/yum.repos.d folder)
suse-extras.repo (likewise)
suse-update.repo (likewise)
packman.repo (likewise)
Then all you do is type
yum update as root and let it do it's work.