I nominate the last track off the soundtrack from Melvin Van Peeble's infamous blaxplotation flick Sweet Sweetback's Baadasssss Song. Track 10 is entitled: "The Man Tries Running His Usual Game but Sweetback's Jones Is So Strong He Wastes the Hounds (Yeah! Yeah! and Besides That He Will Be Comin' Back Takin' Names and Collecting Dues)"

It's a long song title, but not the longest. According to the Wikipedia article on "List of songs with titles of twenty or more words", Christine Lavin on her album Future Fossils has a 95-word track title: "Regretting What I Said to You When You Called Me At 11:00 On Friday Morning To Tell Me That 1:00 Friday Afternoon You Were Gonna Leave Your Office, Go Downstairs, Hail A Cab, To Go Out To The Airport, To Catch A Plane, To Go Skiing In The Alps For Two Weeks. Not That I Wanted To Go With You; I Wasn't Able To Leave Town, I'm Not A Very Good Skier, I Couldn't Expect You To Pay My Way, But After Going Out With You For Three Years, I Don't Like Surprises. (A Musical Apology)"

That must really screw with the liner notes.