Cluny Media is a publishing house dedicated to preserving classic Catholic works of literature. From fiction to theology, they publish it all! If they don’t have a title you’re looking for, their website has a contact form that allows for users to provide suggestions. https://clunymedia.com/
Ever wonder where the customs and traditions surrounding Mass came from? Fr. James L. Meagher explores the answers by investigating how the order of the Mass is rooted in the Jewish Passover celebration. He even travels to the Holy Land to aid in his research and witness the ancient celebrations for himself. https://www.barnesandnoble.com/w/how-christ-said-the-first-mass-rev-james-l-meagher/1133827248
Sophia Institute Press publishes a wide variety of books and videos designed to instruct Catholics of all ages, including resources for teachers and catechists. They are also the publishers behind Benedictus magazine. https://www.sophiainstitute.com/
Published by Tumblar House, A Catholic Quest for the Holy Grail tackles the Catholic elements of the stories of King Arthur and the Holy Grail. The rich Catholic history of these stories creates a far more exciting saga than any mere fiction could hope. https://www.tumblarhouse.com/products/a-catholic-quest-for-the-holy-grail-charles-coulombe
Originally published in 1925, A Roman Catholic Drillbook has been republished for the first time in decades by Romanitas Press. This book contains several easy-to-memorize drills of information about the Bible, Sacred Liturgy, the Sacraments, and much more. Learning the tenants of the Faith has never been easier! http://www.romanitaspress.com/roman-catholic-drillbook
Founded in 1967, TAN Books has earned a reputation for publishing a wide variety of Catholic materials, including writings of the saints. No matter how obscure the title is, TAN Books is bound to have it in stock. https://www.tanbooks.com/
Tumblar House is a Catholic publishing company dedicated to evangelizing through good literature. With both fiction and non-fiction categories, they feature classic authors such as Hilarie Belloc and J. R. R. Tolkien as well as more modern names like Charles A. Coulombe and Solange Hertz. https://tumblarhouse.com/ (As an aside, the webmaster highly recommends William L. Biersach’s Father Baptist mystery series.)