i was attempting to install Rigs of Rods following this howto, http://www.rigsofrods.com/wiki/pages/Installation_Guide but when i attempted to add the repository apt link to /etc/apt/sources.list, it seemed to work until i got this error in synaptic package manager when it was reloading:

The repository may no longer be available or could not be contacted because of network problems. If available an older version of the failed index will be used. Otherwise the repository will be ignored. Check your network connection and ensure the repository address in the preferences is correct.
Code:
Failed to fetch http://apt.rigsofrods.com/Sources  404  File not found
Failed to fetch http://apt.rigsofrods.com/Packages  404  File not found
Some index files failed to download. They have been ignored, or old ones used instead.
here is the results of cat /etc/apt/sources.list:
Code:
 cat /etc/apt/sources.list
# deb cdrom:[Ubuntu 11.10 _Oneiric Ocelot_ - Release i386 (20111012)]/ oneiric main restricted

# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
# newer versions of the distribution.
deb http://us.archive.ubuntu.com/ubuntu/ oneiric main restricted
deb-src http://us.archive.ubuntu.com/ubuntu/ oneiric main restricted

## Major bug fix updates produced after the final release of the
## distribution.
deb http://us.archive.ubuntu.com/ubuntu/ oneiric-updates main restricted
deb-src http://us.archive.ubuntu.com/ubuntu/ oneiric-updates main restricted

## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team. Also, please note that software in universe WILL NOT receive any
## review or updates from the Ubuntu security team.
deb http://us.archive.ubuntu.com/ubuntu/ oneiric universe
deb-src http://us.archive.ubuntu.com/ubuntu/ oneiric universe
deb http://us.archive.ubuntu.com/ubuntu/ oneiric-updates universe
deb-src http://us.archive.ubuntu.com/ubuntu/ oneiric-updates universe

## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu 
## team, and may not be under a free licence. Please satisfy yourself as to 
## your rights to use the software. Also, please note that software in 
## multiverse WILL NOT receive any review or updates from the Ubuntu
## security team.
deb http://us.archive.ubuntu.com/ubuntu/ oneiric multiverse
deb-src http://us.archive.ubuntu.com/ubuntu/ oneiric multiverse
deb http://us.archive.ubuntu.com/ubuntu/ oneiric-updates multiverse
deb-src http://us.archive.ubuntu.com/ubuntu/ oneiric-updates multiverse

## N.B. software from this repository may not have been tested as
## extensively as that contained in the main release, although it includes
## newer versions of some applications which may provide useful features.
## Also, please note that software in backports WILL NOT receive any review
## or updates from the Ubuntu security team.
deb http://us.archive.ubuntu.com/ubuntu/ oneiric-backports main restricted universe multiverse
deb-src http://us.archive.ubuntu.com/ubuntu/ oneiric-backports main restricted universe multiverse

deb http://security.ubuntu.com/ubuntu oneiric-security main restricted
deb-src http://security.ubuntu.com/ubuntu oneiric-security main restricted
deb http://security.ubuntu.com/ubuntu oneiric-security universe
deb-src http://security.ubuntu.com/ubuntu oneiric-security universe
deb http://security.ubuntu.com/ubuntu oneiric-security multiverse
deb-src http://security.ubuntu.com/ubuntu oneiric-security multiverse

## Uncomment the following two lines to add software from Canonical's
## 'partner' repository.
## This software is not part of Ubuntu, but is offered by Canonical and the
## respective vendors as a service to Ubuntu users.
# deb http://archive.canonical.com/ubuntu oneiric partner
# deb-src http://archive.canonical.com/ubuntu oneiric partner

## This software is not part of Ubuntu, but is offered by third-party
## developers who want to ship their latest software.
deb http://extras.ubuntu.com/ubuntu oneiric main
deb-src http://extras.ubuntu.com/ubuntu oneiric main
deb http://apt.rigsofrods.com/ /
deb-src http://apt.rigsofrods.com/ /
all help appreciated..