Are the sites developed? did they ever have ads on? theres nothing wrong with selling legitimate fan sites as i am aware, bar the fact they could say you made a profit on there name, talk to DNquest he knows alot about this kind of deal.
Yes, you could be held liable and a TM holder could come after you under the ACPA to collect damages. Does this happen, not really.
Welcome to the community, but there is much to learn, I would suggest reading my sig, it will help you out greatly since there are so many scenarios, just about all of them have been covered here at some point. You just have to read for a bit./
DNQuest has a far better understanding of this stuff than most, and most lawyers, unless they have specialized in this area for a while, are pretty clueless.
Thanx for the kind words, but there are much better here, I just have no life and able to post more at times. Any delicate situations, please, contact the esteemed attorneys who frequent the boards here. I can only regurgitate what I learned over the years from the smart people and try to give my honest non-biased opinion (and at times, as I am told, harsh and cold).