These ebuilds come from http://proaudio.tuxfamily.org/wiki.
If you have some problems, go to the official site first.
faustworks : IDE for the Faust dsp programming language ( http://www.fauste.grame.fr/ )
lv2-c++-tools : some tools and libraries that may come in handy when writing LV2 plugins ( http://ll-plugins.nongnu.org/hacking.html )
premake : A makefile generation tool ( http://industriousone.com/premake )
Add an ebuild in portage :
The ebuild is now in the portage tree.
You can also use layman : emerge layman then layman -a pro-audio
For Paludis use this rsync : rsync://gentoo.zugaina.org/pro-audio-portage
If you have a problem : ycarus(-at-)zugaina.org