e-Books

In case any of the sites are blocked or inaccessible, Change DNS to 1.1.1.1 or use GoodByeDPI / PowerTunnel.

_{Use an e-Book manager like Calibre to manage and convert your e-Books, it provides a good interface.}

General E-Books

Easily verify the status of the largest Libraries online using SLUM: The Shadow Library Uptime Monitor.

Anna’s Archive .org | .li | .se - Search Engine that indexes many big Libraries including libgen, Z-Lib and Sci-Hub.
Z-Library - The Library is also accessible through Tor. Requires Sign-up.
LibraryGenesis .rs | .is | .st - A Shadow library for access to journal articles, academic and general Books, Comics, Audiobooks, etc.
Mobilism (.me) | .org - Forum. Requires Sign-up.
MYWAREZ.ORG - Forum. Requires Sign-up.
The-eye - Many e-Books and calibre libraries.
OceanofPDF
WeLib
My Anonamouse - Has a lot of content, including niche e-Books and audiobooks. Friendly community and mods. An easy to get into Private Tracker. Requires Sign-up.
Be sure to check our PT page for more info regarding Private Trackers.
Project Gutenberg - Legally free e-Books.

Sci-Hub (.se) | .st | .ru
Sci-Hub X Now! - Opens the Sci-Hub page for the article you want to read.
Zotero Scihub - Addon for Zotero and Juris-M to automatically download PDFs from Sci-Hub.
SciMag - Scientific Articles section of LibGen.
Free Full PDF
Freetechbooks
r/Scholar - If you can't find an article anywhere, you can request it in this subreddit.

Rave Book Search Engine - A search engine that indexes many Comic, e-Book and Audiobook sites.
Archive.org & Open Library - Has a lot of niche historical content.

DeDRM - Tools to be used with Calibre to remove the DRM of e-Books from various retailers.
Bypass Paywalls Clean for Chrome & Firefox - Bypass News Article paywalls.
Unpaywall - When you view a research article, Unpaywall automatically looks for a copy in its index. If it finds one, click the green tab to read the article.
Archive Buttons | Remove Paywalls - Remove Paywalls from greedy News sources that ask for money to read their Articles.