Who are the well known professional sports coaches/managers who never actually
played their respective sport (e.g., football, baseball, basketball)?

Do you mean:

never played their respective sport professionally or never played
their respective sport at all?

Will probably influence the answer...

Have a good day.

Karl Adam, German Olympic rowing coach:
http://en.wikipedia.org/wiki/Karl_Adam_(rowing_coach)

"Who are the well known professional sports coaches/managers who never actually
played their respective sport (e.g., football, baseball, basketball)?"

In the NFL Vince Lombardi, George Allen, Don Shula, Dennis Green, Bill
Walsh, John Madden, Marv Levy, Mike Holmgren and Jon Gruden all never
played the game at the pro level. All played football in college at
some level.

Red Auerbach the legendary coach of the Boston Celtics never played
pro basketball, although he played in college, interrupted by WW II.

MLB WS managers who never played in the majors:
Earl Weaver, Tony LaRussa, Joe McCarthy, Whitey Herzog