Here is a list of online Catholic retailers who sell homeschooling materials:
Adoremus Books carries over 20,000 items for Catholics and homeschoolers. Catholic books, movies, gifts, and educational supplies. Your one-stop shopping place for Catholic material.
Purveyors of vintage children’s and traditional Catholic books. A Catholic homeschool family with 10 children themselves, the Kellers buy and sell books that enrich, nurture, and inspire.
In addition to publishing their own titles, Seton carries hundreds of titles from other publishers–everything from pre-school workbooks to high school novels, support books for parents or DVDs for the whole family.
Known for their significant discounts, Sacred Heart Books is a popular supplier of a wide array of homeschooling materials and books.
One of the official suppliers for the Mother of Divine Grace curriculum, Emmanuel Books also has a huge catalogue of children’s titles.
This list is not exhaustive, but highlights most of the more professional and larger retailers.