This is a great guide for getting Gentoo on the Pi. I did not see any stage4 installs available so I wanted to make one for the public to help save time on the Pi. If you follow all the steps on the Wiki yourself, it will take a few hours to accomplish the same steps.

Instructions:

Download the stage 4: https://www.dropbox.com/s/7m0dilz3me76mr8/stage4-01232013.tar

[insert url here]

Partition SD card :
100 MB -> /boot (/dev/mmcblk0p1) (Windows partition)
2GB or more -> / (/dev/mmcblk0p2) (Linux )

mkfs.vfat /dev/mmcblk0p1
mkfs.ext4 /dev/mmcblk0p2

Extract stage4-01232013.tar.gz somewhere

Mount /boot somewhere and copy the files in “boot” to it from the stage4 tar file.
Mount / somewhere and move everything else there.
Download the latest portage snapshot per the Gentoo Guide and extract it to usr/ on your new / .

Unmount everything and turn on your Pi.