In the ’70s and ’80s, Louisiana’s LeRoux released five major-label albums. The band’s biggest hit, “Nobody Said It Was Easy,” reached the national Top 20. Two other songs, “Addicted” and “Carrie’s Gone,” received radio play and MTV exposure.

But “New Orleans Ladies,” LeRoux’s most famous song in Louisiana, never reached the Top 40. Lack of national success didn’t stop the bittersweet ballad, written by LeRoux bassist Leon Medica and Bogalusa songwriter Hoyt Garrick, from becoming a ubiquit...