Anyone have the audio book MP3's? I'd also like to know a good place to start with these. My knowledge of the 40K universe is fair but not extensive,
Avoid the HH series at all costs.
Titanicus is a pretty good starting point, mood wise, also has the best author for War-Porn if that's what you're into
Read Ciaphas Cain HERO OF THE IMPERIUM
at any point you feel it getting too grimderp.