Installing software offlinefrom DVD in Fedora 15

make a dir to hold the RPMS and copy them from your DVD (mounted at /mnt/dvd I assume here) to this dir:

mkdir -p /F15repo/RPMS
find /mnt/dvd/ -name '*.rpm' -exec cp -v {} /F15repo/RPMS/ \;

Create the repo (might need to 'yum install createrepo' first
createrepo /F15repo

put the below contents in a file called /etc/yum.repos.d/F15local.repo
[F15local]
name=Fedora $releasever - $basearch - Local
baseurl=file:///F15repo/
enabled=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-fedora


now do this to make sure you can see your new F15local repo:
yum repolist

now list the available RPMS:
yum --disablerepo=* --enablerepo=F15local list available