Laxmi Bachanalaya
Legally available public-domain books and openly licensed reading materials.
Virgil Markham
Gertrude W. Morrison
Mary Roberts Rinehart
Emile Gaboriau
James Otis
Edgar Wallace
E. Phillips Oppenheim
L. P. Wyman
Allan Pinkerton
Edith Lavell
Melvin L. Severy
Edward Stratemeyer
Jean-Eugène Robert-Houdin
Anna Katharine Green
Jr. Horatio Alger
Guy Boothby
William Le Queux
Ramalho Ortigão and Eça de Queirós
John Ironside
Auguste Groner
Various
Melville Davisson Post
Hilaire Belloc
Frank H. Spearman
These books are free to read. Each is in the public domain in the United States; check your own country's rules before you copy or share one.