The rpmfusion-release package you are trying to install if for F14. F11 is long EOL and if you want to use it you'll have to do quite a bit finagling to get things setup as far as package repositories go. The F11 repos are now in the archives, and you'll need to manually edit your fefora.repo and fedora-updates repo files to direct yum to those archives.
For the rpmfusion repos.. start by installing the repo releases that are for F11 (not listed on their web page, but they are still intact.
su -c "rpm -ivh http://download1.rpmfusion.org/free/fedora/releases/11/Everything/i386/os/rpmfusion-free-release-11-1.noarch.rpm http://download1.rpmfusion.org/nonfree/fedora/releases/11/Everything/i386/os/rpmfusion-nonfree-release-11-1.noarch.rpm"
Don't worry about the "i386" if you're using a 64 bit install, the repo files will automatically direct you to the correct "arch".
There are several threads on the forum here showing how to modify the Fedora repo files to point to the archives. Search for them. I'm not on my F12 machine at present, so I can't just copy 'n paste for you at the moment.
---------- Post added at 08:39 PM ---------- Previous post was at 08:31 PM ----------
You will not find newer nvidia drivers, or newer anything else, on these stagnant repo sites. The last "updated" kmod-nvidia" from the F11 RPMFusion site is kmod-nvidia-190.53-1.fc11, a far cry from the current 290.10 release. If you want anything newer than 190.53, you'll have to install the package from Nvidia.