Originally Posted by itimpi
You can already do this if you create a rar archive to hold all the files making up the audiobook.
However as audiobooks are so much larger than ebooks, I prefer to keep them separate to my ebook library.
True - I just tried this (using a zip file) and double clicking in calibre opens the archive from whence I can play the files. However, as you say this means that I would have to put large audiofiles into calibre which is undesirable.
So I created a vlc playlist, which is basically just an xml file, and added that to calibre. Double clicking fired up vlc for me and the .xspf file is small enough that I'm not too concerned about it being duplicated. For the sake of purity I would prefer it was a link - and I could probably arrange that manually on linux - but it is not a major issue.
So for me that is job done. I can now see from calibre whether I have an audio version of my book and even fire it up, but without having to duplicate the audio files which would normally reside in my squeezebox audio libraries.
Thanks itimpi for the nudge which gave me the facility I was looking for without me having to do any significant work!