Anyone know the title of the episode where Fred finds a copy
of a rare 78 rpm record by "Blind Lemon Jefferson," and winds
up sitting on it at the end?

"The Blind Mellow Jelly Collection" Season 3 -Episode 3

"I WANT MY DADDY'S RECORDS!"
http://www.youtube.com/watch?v=jv7RkH-vTcM

I think that was supposed to be a take of the name of Blind Lemon Jefferson.

By the way Blind Lemon Jefferson was a real blues singer from the 1920's. He did a song called "See That My Grave Is Kept Clean" that Bob Dylan later covered. If yall are into early aucustic blues then check this guy out.