If you don't know who John D. Loudermilk is, then you must by younger than I am. Even at that, you might have heard one of his songs. He wrote a lot of good ones.
John D. Loudermilk - bio, pictures, lyrics, songs - extensive webpages about the man and his music: "John D. Loudermilk was born on March 31, 1934 in Durham, North Carolina. One of the most productive Nashville songwriters in the 1960s, he acquired a prominent place in the rock, teen, pop and country music of that decade."