Why not try a DT and Forum search putting "@humor" or "@parody" or "@funny" in the box [without the quotation marks]? You'll find tons of good stuff. There are threads on "nonsense lyrice," "parodies," etc.

The Limeliters did do a great job on "M'deira, M'Dear," but the original was Flanders & Swann, who wrote lots of hilarious stuff [e.g., "The Hippopotamus Song," "Tonga."

Then there's Bryan Bowers, Tom Lehrer, Tom Paxton, Spike Jones, Homer & Jethro, Bob Rivers, and a bunch of others whose names are escaping me right now.

Keep laughing!

Genie