Yum install anomaly and yum config question

[Gerry Tool]

I did a fresh anaconda install of FC3 and an anaconda update of FC2 -> 
FC3.  The fresh install installed the after-install updates properly 
using 'yum update'.

The updated FC2 -> FC3 did nothing when I executed 'yum update'.  I 
discovered that the update install left me with the FC2 yum.conf in 
place, so I copied the one from the fresh install and 'yum update' then 
worked just fine.  I would have expected the yum.conf to be replaced 
with one that would work with the updated FC3 during the anaconda install.

Question:  How can I add .repo files to /etc/yum.repo.d to access the 
livna and Fedora US repositories with the new yum?  I tried copying a 
section of the FC2 yum.conf file into a file and placing it in the 
directory, but it failed with

Trying other mirror.
Cannot open/read repomd.xml file for repository: fedora-stable
failure: repodata/repomd.xml from fedora-stable: [Errno 256] No more 
mirrors to try.

There is probably a document somewhere that I don't know about telling 
how to do this.

Thanks.

Gerry Tool