TOD:
Books:
Lew Archer
Philip Marlowe
Nick and Nora Charles
Perry Mason
Too many Agatha Christie characters to detail here.
Harry Bosch
Travis McGee (did I spell that right?)
Film or TV
Peter Falk as Colombo
Paul Newman as Lew Archer, er, Harper
Almost anybody who played Marlowe (including Elliott Gould)
Raymond Burr as Perry Mason
Margaret Rutherford as Miss Marple
David Suchet at Poirot
William Powell and Myrna Loy as the Charleses.