Thanks to Marty McFly two of the three Carrie Fisher hosting broadcasts have been digitized by the :F:L:I:M:S:I:P:L:A:S:T: :D:A:T:A:B:A:S:E:.
After finding the usenet request, Marty McFly offered up his tapes. ('Star Wars and 'Return of the Jedi') Many Thanks. But still looking for Empire. Marty's fairly certain his copy hasn't been thrown away, but it's unlocatable at the moment.
All three movies use the same set, so the Fisher hosting segments are not as vibrant as Billy Dee's but she was either allowed more room to speak her mind or took advantage of the situation, so the segments are a little more interesting.