"I was wondering what one could do to stop people from downloading pornography of a minor that was put on lime wire without their consent."

probably nothing (what was the minor doing making porn anyway)

"Is there any way to stop something like that other than taking legal action?"

against who, the minor for making porn?

"Who would I need to contact?"

the minor's parents maybe?

"I have a friend who has been exploited on this site without her consent and is underage."

but did she consent to makiing the (underage) porn?

"It has now gone all over the country and it needs to be stopped. If necessary I and several others are prepared to file a lawsuit against whoever this involves."

why was is even started if she is underage? who will you file the lawsuit against? the whole country? or the minor for making the porn?

"If a reply is posted to this, I will give further necessary information so that this video can be pulled from this and any other site it may be on. If not, legal action will be taken."

what's the name of that file? i'd love to see it!