I decided to try an audiobook on my iPod. They don't offer many at the iTunes store, and I thought I'd like to try something lightweight to begin with. I downloaded 'Men at Arms' by Terry Pratchett. It's read by Nigel Planer, and about eight hours long. At first I thought 'I'm not going to like this' because of course the voices he uses are quite different from the voices in my head (when I read the book), but by the time I was an hour or so in, I had got used to it.
I have to admire the clever way Planer verbally distinguishes about twenty different characters, conveying class, species, age, gender etc. And he swaps rapidly between them.
Also he doesn't give the female characters silly high-pitched or breathy voices. Interestingly the sexy characters (Vimes & Angua) both sound as if they've got blocked noses. Not sure what that is supposed to convey.
I might try Stephen Fry reading The Prisoner of Azkhaban next, though it's quite expensive.