Constantin describes in this article how to create an DVD-Audio disc on Linux/Solaris (and also emphasizes the difference between DVD-Audio and DVD-Video).
I assume that most people who are interested in DVD-Audio know that there are also commercial DVD-A solutions out there, like DiscWelder.
However, for the task at hand Constantin would not have needed to create a DVD-Audio disc, but instead could have simply used his favorite DVD-Video authoring tool and create a stereo 96kHz/24bit LPCM track on a DVD-Video. All fully compatible DVD-V players must support this format, thus you do not have to resort to DVD-Audio.
This is obviously different for multi-channel formats where the DVD-Audio format is the only viable alternative. For high-resolution, multi-channel tracks, you will also need an MLP encoder … and here we are talking about some serious licensing fees.
PS: Here is an overview on the DVD-Video audio capabilities.