The information wants to be free!
Great books which do not need registration based shilling techniques for your hacking careers:
https://mitpress.mit.edu/sicp/full-text/book/book.html
http://www.paulgraham.com/onlisp.html
https://gustavus.edu/+max/concrete-abstractions.html
https://www.cs.cmu.edu/~dst/LispBook/
Open and Free FTW!