I am currently listening to Susanna Clarke’s Jonathan Strange & Mr Norrell on audiobook. Luckily, to start with, it is an excellent book. The audiobook is narrated by Simon Prebble and I can’t think of anybody who could possibly have done a better job of narrating this, it is spot on in every way. I had never heard of Simon Prebble before and still know little of him but will look at what other books he has read and would not hesitate in downloading another.
There is a page on the site with a few more suggested fantasy audiobooks
http://www.fantasybookreview.co.uk/articles/audiobooks.html