This is what I got. And you should be in /usr/src/modules/nvidia-kernel/nv in order to build it by using make if you arent going the make-kpkg route.
Line commented out by installer because it failed to verify:
deb
http://us.archive.ubuntu.com/ubuntu/ dapper main restricted
# Line commented out by installer because it failed to verify:
#deb-src
http://us.archive.ubuntu.com/ubuntu/ dapper main restricted
## Major bug fix updates produced after the final release of the
## distribution.
# Line commented out by installer because it failed to verify:
deb
http://us.archive.ubuntu.com/ubuntu/ dapper-updates main restricted multiverse
# Line commented out by installer because it failed to verify:
#deb-src
http://us.archive.ubuntu.com/ubuntu/ dapper-updates main restricted
## Uncomment the following two lines to add software from the 'universe'
## repository.
## 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
## universe WILL NOT receive any review or updates from the Ubuntu security
## team.
deb
http://us.archive.ubuntu.com/ubuntu/ dapper universe multiverse
# deb-src
http://us.archive.ubuntu.com/ubuntu/ dapper universe
## Uncomment the following two lines to add software from the 'backports'
## repository.
## 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/ dapper-backports main restricted universe multiverse
# deb-src
http://us.archive.ubuntu.com/ubuntu/ dapper-backports main restricted universe multiverse
# Line commented out by installer because it failed to verify:
deb
http://security.ubuntu.com/ubuntu dapper-security main
# Line commented out by installer because it failed to verify:
#deb-src
http://security.ubuntu.com/ubuntu dapper-security main
deb
http://security.ubuntu.com/ubuntu dapper-security universe
# deb-src
http://security.ubuntu.com/ubuntu dapper-security universe
deb
http://packages.freecontrib.org/ubuntu/plf/ dapper non-free free
deb
http://www.debian-multimedia.org testing main
apt-cache search nvidia-kernel
linux-restricted-modules-2.6.15-23-386 - Non-free Linux 2.6.15 modules on 386
linux-restricted-modules-2.6.15-23-686 - Non-free Linux 2.6.15 modules on PPro/Celeron/PII/PIII/PIV
linux-restricted-modules-2.6.15-23-k7 - Non-free Linux 2.6.15 modules on AMD K7
nvidia-kernel-common - NVIDIA binary kernel module common files
nvidia-kernel-source - NVIDIA binary kernel module source
nvidia-legacy-kernel-source - NVIDIA binary 'legacy' kernel module source