Available in a git repository.
Repository: tove
Browsable repository: tove
Author: W. Trevor King

I wanted to install ikiwiki on my home box so I could test-compile this blog before pushing commits to the live server. Gentoo's ikiwiki ebuild (bug 144453) is in Torsten Veller's overlay, so I forked his overlay and bumped the Ikiwiki version number. I've emailed Torsten with a merge request, but haven't heard back yet. Anyhow, add this layman.xml to your /etc/layman/layman.cfg overlays listing and run:

# layman -a tove-wtk

Then:

# emerge -av ikiwiki

and you're off!

Update: Torsten just pushed the ikiwiki ebuild into Portage. There is no longer any need to mess around with layman if you want to install ikiwiki.