The Maharishi (Everyone's In Love With You, and several others, indirectly.)
"The TM Song" mentions his name.
The number of songs which are
actually about real people, as opposed to just mentioning them, as I've listed, is rather small. Top of my head...
"Judy", "Surfer Girl" - Judy Bowlles
"A Young Man Is Gone" - James Dean
"Fun, Fun, Fun" - Denny's squeeze of the time, allegedly
"The Little Old Lady From Pasadena" - Katherine Milner
"The Girl From New York City" - Leslie Gore, allegedly
"I'm Bugged At My Ol' Man" - Murry Wilson
"Anna Lee, The Healer" - Anna Lee ?? (there was an article about her in
Psychic News back in the 70s)
"Marcella" - the noted masseuse
"Susie Cincinnati" - Joellyn Lambert
"Johnny Carson" - guess...
"The Night Was So Young" -

"Peggy Sue" - Peggy Sue Gerron (orig. Cindy Lou Kaiter)
"My Diane" - Diane Rovell
"Somewhere Near Japan" - Mackenzie Phillips
Borderline cases are...
"Spirit Of America" - more about the car than Craig Breedlove
"Caroline, No" - Carol Mountain, Marilyn Wilson, Asher's former gf... you pick
"Passing Friend" - Marilyn (Boy George's sometime squeeze)