Where would one find a library of Chinese classics that have never been translated into English?
several free resources, depend on where you’re:

the internet archive has a cadal (china-us million book digital library project) collection, which contains 89000+ books. most books of imperial collection of four (四庫全書) are included, plus many literatures of yore.

this collection alone should suit your need, unfortunately, it’s blocked in “that area” now.

for buddhism texts, try the 漢文大藏經


  to produce automated translations


forget it, no one can 


  into modern, simplified Chinese characters


even the communists do not do it, find &amp; read carefully what’s the rules of the simplification.

have fun :)