Here is a packaging of Linux 2.6.28 that I made for my Fujitsu LifeBook P8010 running Ubuntu 8.10.
The packaging is minimal. It does not do all the careful checks that proper Debian/Ubuntu kernel packages make about installing over or removing a running kernel. Use at your own risk. However, it does manage the initrd file and grub boot menu.
My only customization is to add the (non-free) Intel Wireless 4965 microcode to the linux-firmware package.
Updated 5 February 2009 with 2.6.28.3 and latest iwlwifi firmware.
linux-2.6.28.3_2.6.28.3-3_i386.deb
linux-firmware-2.6.28.3_2.6.28.3-3_all.deb
Older version; don't use this.
linux-2.6.28_2.6.28-56_i386.deb
linux-firmware-2.6.28_2.6.28-56_all.deb