I think the ultimate problem with Law & Order is art for the first ten or so seasons of the original series. I have publicity shots for all of criminal intent and special victims and Conviction, but since the first ten seasons of law & order are on the older side there isn't much art on the net in high quality.

I have a couple hundred or a thousand screen captures from the series, but only from the seasons released on dvd so far (1-6, +14 on the original series). Also, art on Trial by Jury seems to be a bit hard to come by.