If you like mysteries where all of the main characters are stuck in some kind of confined environment (a large, scary, old house) trying to solve some kind of crime or love the Agatha Christie novels when Poirot dramatically explains the crime's solution at the end of his books to the group of suspects, should enjoy these authors/characters:

Margery Allingham's Albert Campion 

Carolyn Hart's Henrie O'

M. C. Beaton's Agatha Raisin 

Ngaio Marsh's Inspector Alleyn 

Susan Kandel's Cece Caruso

Alexander McCall Smith's No. 1 Ladies' Detective Agency

David Roberts' Verity Browne & Lord Edward Corinth