Konversation is available in the extra repository.
Type as root:
pacman -S konversation
Konversation Git PKGBUILD
If you want to build the latest development version of konversation you can use this PKGBUILD from the AUR:
Konversation SVN PKGBUILD (deprecated)
If you want to build an older development version from SVN you can use this PKGBUILD from the AUR: