Here is a list of resources to get started on learning about both the Montessori Method (which is conveniently free through tables) and Catechesis of the Good Shepherd.
Dr. Maria Montessori publications
"Spontaneous Activity in Education" free on kindle and iTunes
"The Montessori Method" free on iTunes
"Dr. Montessori's Own Handbook" free on iTunes
"The Absorbent Mind" free on kindle
Religion Taught the Montessori Way
"The Religious Potential of the Child" by Sofia Cavalletti is all about the Catechesis of the Good Shepherd and is available to purchase online, but not free.
"The Child in the Church" by Dr. Maria Montessori can be purchased online, but also not for free.
Association Montessori International Parent Resource List
American Montessori Society Family Support Materials List
Catechesis of the Good Shepherd
Please let us all know about other recommended resources in the comment section below.