The Comedian and his assistant can be found in Lynna City standing in front of the house across the river. While his assistant cannot find anything funny during the troubles which Labrynna is experiencing, the Comedian will continue to tell jokes, not acknowledging the never-ending day that has befallen Labrynna.
In Symmetry Village, Link can trade the Dumbbell to the Thin Man in exchange for a Cheesy Mustache. Link can then trade the Cheesy Mustache to the Comedian, who will give Link the Funny Joke in return. The Cheesy Mustache is the 7th item in the Trading Sequence, which leads to Link acquiring the Noble Sword.
Comedian and his Assistant in Lynna City.