How to hide audio, video or images at gallery? Is there anything to be done if I don't want particular folder containing audio, video or images being displayed at gallery or any audio application ?

Actually I am facing problems since my audio books are also being listed at all songs playlist of music players.

Any suggestions ?
You find a possible solution in many posts around here -- if you know what to look for, that is...

Responsible for files turning up in the gallery etc. is the media-scanner, so you have to keep that one from processing the directories you want to ommit. The usual approach for this is placing a file named .nomedia (note the starting dot) into all directories you want to exclude (in your case, the ones containing your audio books). Simply put, this tells the media-scanner: "No media here, just skip this folder".