You can try this link and follow the instructions:
It works fine in my computer when I successfully installed it.
Go to http://www.nvnews.net/vbulletin/showthread.php?s=8ef6fcfc7083462c3969f5bd80cee8e1&t=122606
Select and click Desire Nvidia Version [173,96,etc], then click the FTP link
Download the .run file (ex. NVIDIA-Linux--pkg.run)
Run the file in the terminal -> sh NVIDIA-Linux--pkg.run
Another solution that I found out is this :
In my case, Im using Linux Mint, but i guess that all repositories in this os is still the same as in Ubuntu, Using Linux Mint Maya (Ubuntu 12.04 equivalent in precise) I followed this forum
Since Nvidia-96 is not available on any higher versions (precise and upper i guess), in this forum, they tried to get the Nvidia package to a lower ubuntu version (oneiric) and use it to their current OS and downgrade their xorg to oneiric.
Now these steps are still working in my system, and I'm using oneiric nvidia-96.