From what ive heard on the news etc, people are turning creating these images/videos into big money business, if people werent paying to download them then they wouldnt be doing so and the poor kids in the scenes being abused wouldnt be there in the first place.

So IMHO, they are all guilty, both those selling the images and those buying them, if people didnt pay to use these websites that Chris Langham did then there would be no reason for those websites to carry on abusing kids for profit.