NVU is now called Kompozer and is in the Ubuntu repo.
knitebane@laptop:~$ apt-cache search kompozer
kompozer - Complete Web Authoring System
kompozer-dev - KompoZer development files
nvu - Transition package for Nvu --> KompoZer fork
nvu-dev - Transition package for Nvu --> KompoZer fork (development files)
Can you tell I have been living in the AIX / WAS world for awhile ;)... While it is in Ubuntu it was not on Fedora Core6 (last time I checked..)