University of Notre Dame Catholic Pamphlets Collection (3,903 scans!)

[Geremia]

University of Notre Dame Catholic Pamphlets Collection
They span from 1800 to 2010, but the post Vatican II ones (e.g., the 1969 Catholics and Masons: Now Good Friends!) are not recommended.
There are catechisms (like the New St. Joseph's Baltimore Catechism) and many other good books. They're also categorized.

[Wenura]

Not working

[Geremia]

Not working

Yeah, they took it down awhile ago. Perhaps someone complained about some or all of the books possibly violating ©.