http://gen.lib.rus.ec (Working as of 5/30/17)

http://textbooknova.com (Working as of 5/30/17)

http://www.gutenberg.org (Working as of 5/30/17)

http://ebookee.org (Working as of 5/30/17)

http://www.manybooks.net (Working as of 5/30/17)

http://www.feedurbrain.com/forum/forum.php (Working as of 5/30/17)

http://www.manybooks.net (Working as of 5/30/17 - but seems sketchy, wants you to sign up for everything and never seems to get you to the book you want)



http://www.giuciao.com (Appears to be down/domain placeholder as of 5/30/17)

http://www.feedurbrain.com (Working as of 5/30/17)

http://oll.libertyfund.org/index.php?option=com_content&task=view&id=380 (Working as of 5/30/17)

http://www.alleng.ru/ (Working as of 5/30/17 - However, site is entirely in Russian)

http://www.eknigu.com/ (Appears to be down/domain placeholder as of 5/30/17)

http://ishare.iask.sina.com.cn/ (Working as of 5/30/17 - However, site is entirely in Chinese)

http://2020ok.com/ (Working as of 5/30/17)

http://www.freebookspot.es/Default.aspx (Working as of 5/30/17)

http://www.freeetextbooks.com/  (Working as of 5/30/17 - appears to require Bittorrent to download & You must sign up and register to download)

http://onebigtorrent.org/ (Working as of 5/30/17 - appears to require Bittorrent to download - No username/password required)

http://bookzz.org/ (Appears to be down as of 5/30/17) - MOVED to http://b-ok.org/

Guide for Finding Textbooks (tutorial): https://www.reddit.com/r/Piracy/comments/3i9y7n/guide_for_finding_textbooks/ (Link is over 1 year old.  I do not have the time/energy to check all the URLs this person has posted as sources, but if you would like to, please HMU on Twitter @pogue25 or leave a comment down below in the Disqus comment system.)

http://forums.mvgroup.org (Working as of 8/1/16 - appears to require Bittorrent to download & mandatory sign up [Note: I remember this site as being a Bittorrent site for mainly documentaries]

http://audiobookle.com/ (Working as of 5/30/17 - appears to require Bittorrent to download - I cannot determine if this is a legitimate site or if it is trying to get you to sign up to download spyware.  I searched through multiple anti-virus sites to try and determine if it was legitimate and all said it was okay, except NetCraft which gave it a rating of 1/10 and Web of Trust which gave it a 50% rating)
Netcraft: http://toolbar.netcraft.com/site_report?url=audiobookbay.me
Web of Trust: https://www.mywot.com/en/scorecard/audiobookbay.me

*** USE AT YOUR OWN RISK ***

Free full published studies: http://sci-hub.cc/ (Working as of 5/30/17 - Follow them on Twitter @Sci_Hub as they keep getting taken offline)

Open Source College Textbooks: https://openstax.org/subjects (Working as of 5/30/17)

Open Textbooks: http://collegeopentextbooks.org/ (Working as of 5/30/17)

Free Public Domain Audio Books https://librivox.org/ (Working as of 5/30/17)

You can also rent textbooks for very cheap from Amazon. They ship you a copy of the book and you mail it back to them once the semester is over and you save a LOT of money.  You can even download them digitally to use on Amazon's Kindle reader, which you can download for iPhone or Android. As a student, you're eligible for 50% off Amazon Prime (free shipping, Amazon's music service which is similar to Spotify or iTunes, their movie watching service, which has about the same selection as Netflix) and you get free shipping on most everything.  Even if you're not a prime member, you get free 2 day shipping on textbook rentals and can make $5 if you tell a friend about the service. http://amzn.to/2ah1AHw (Working as of 5/30/17)

Original source: http://s.imgur.com/gallery/il8o8xF  The actual original post seems to be a Reddit post from 5 years ago with a little more information, but hasn't been updated since, as far as I can tell. https://redd.it/hrgmv 
UPDATE: A more recent post from 1 year ago: https://redd.it/2eguxy

Here is another guide for finding free text books, however, I cannot vouch for whether or not any of the methods work: https://redd.it/3i9y7n

http://gen.lib.rus.ec/
*

http://en.bookfi.org/
*

http://bookzz.org/
*

http://forum.mobilism.org/
*

http://tuebl.ca/books/
*

http://avxhome.se/ebooks/
*

www.4shared.com/
*

http://mediafire.com/
*

http://ipmart-forum.com/
*

http://ebook3000.com/
*

http://freebookspot.es/
*

http://demonoid.ph/
*

http://ebookee.org/
*

http://kat.cr/
*

http://www.downeu.org/ebook/
*

https://onebigtorrent.org/torrents/
*

http://manybooks.net/titles/
*

http://freshwrap.ws/
*

http://www.plentyofebooks.net/
*

http://book.pdfchm.net/
*

http://www.freebookspot.es/
*

http://www.feedurbrain.com/forum/
*

http://ebookbrowsee.net/
*

http://2020ok.com/books/
*

http://librs.net/
*

http://thepiratebay.la/torrent/
*

http://bitsnoop.com/
*

http://www.giuciao.com/books/
*

http://books.tr200.org/
*

http://booksc.org/
*

http://club.topsage.com/
*

http://ebookjunkie.com/
*

http://nips.djvuzone.org/
*

http://pdf-giant.com/
*

http://manybooks.net/
*

https://www.scribd.com/
*

http://freecomputerbooks.com/
*

http://www.freetechbooks.com/
*

http://www.onlinefreeebooks.net/
*

http://www.onlineprogrammingbooks.com/
*

http://www.ebooklobby.com/
*

http://bookboon.com/
*

https://www.reddit.com/r/eebooks/*

https://www.reddit.com/r/mathbooks/*

https://www.reddit.com/r/csbooks/*

https://www.reddit.com/r/physicsbooks/*

ZLibrary (still working)

https://www.reddit.com/r/econbooks/

https://www.reddit.com/r/csbooks+econbooks+mathbooks/new/?sort=new

* http://www.freebookspot.club/

* http://libgen.li

*Just Another Library (TOR Only): http://libraryfyuybp7oyidyya3ah5xvwgyx6weauoini7zyz555litmmumad.onion/ (Shoutout to /u/woof for the link!)
* If you want to access this archive, you'll need to download the TOR browser, which is actually very easy. You simply download it, install it, and access it and you're on the dark web. Download TOR browser: https://www.torproject.org/download/
* Free chemistry Textbooks https://collegelearners.com/university-chemistry-textbook/
* Guide for finding textbooks: https://www.reddit.com/r/Piracy/comments/3i9y7n/guide_for_finding_textbooks/
* Links to help you find PDF versions of textbooks: https://imgur.com/r/Piracy/y7KXKyG
* Google Custom Made Search Engine for eBooks (triggers a lot of AV and blocklists for some reason): https://cse.google.com/cse?cx=011394183039475424659:5bfyqg89ers


Bittorrent is easier to use than you think.  If you can run Java, here is a web based BT client: http://www.bitlet.org
You can also run BT via a web browser using the Google Chrome extension JSTorrent https://chrome.google.com/webstore/detail/jstorrent/anhdpjpojoipgpmfanmedjghaligalgb?hl=en (However, it costs $3)
2016 Getting Started with Bittorent guide: http://netforbeginners.about.com/od/peersharing/tp/Torrent-Download-Guide.htm you will probably also need to forward the port in your router, so visit https://portforward.com/

Alternately, here are two other web based Bittorrent clients:
1) WebTorrent https://webtorrent.io/
2) βTorrent https://btorrent.xyz/

They will, however, be slower than regular executable Bittorrent clients, such as these:
1) The Top 10 Best Bittorrent Clients for Windows: http://www.techradar.com/news/the-best-free-torrent-client
2) The Top 7 best Bittorrent Clients for Mac: https://mac.eltima.com/best-torrent-clients-for-mac.html

If you have more sites to contribute, please HMU on Twitter @pogue25

REMEMBER AARON SWARTZ AND HIS FIGHT! INFORMATION SHOULD BE FREE!
SIGN THE PETITIONS TO LOWER COLLEGE TEXTBOOK PRICES:
http://petitions.moveon.org/sign/lower-college-textbook
http://www.textbookrebellion.org/
http://studentpirgs.org/campaigns/sp/make-textbooks-affordable

Create your own petitions on change.org and put the word out! 
College textbooks are the biggest monopoly on higher education and prevents many people from affording getting degrees.

*** ARTICLES ***
College textbooks are a racket https://www.washingtonpost.com/news/monkey-cage/wp/2015/10/21/college-textbooks-are-a-racket/
Why Are College Textbooks So Absurdly Expensive? http://www.theatlantic.com/business/archive/2013/01/why-are-college-textbooks-so-absurdly-expensive/266801/
College Textbook Prices Have Risen 1,041 Percent Since 1977 http://www.nbcnews.com/feature/freshman-year/college-textbook-prices-have-risen-812-percent-1978-n399926
College Textbook Prices Increasing Faster Than Tuition And Inflation http://www.huffingtonpost.com/2013/01/04/college-textbook-prices-increase_n_2409153.html