ROTFL! Scribd is legitimate--a social document sharing site. New material is free, but there is a subscription for accessing archived stuff.
If you want to download pirated material of all media, you can use a bit-torrent client like µTorrent ( http://www.utorrent.com/ ) and a tracker like Pirate Bay ( http://xrl.us/bm8gpy [Link to thepiratebay.se] )
For example, here is a torrent containing ALL of the books on the NY Times bestseller list in both epub and mobi formats:
http://thepiratebay.se/torrent/7203135/NY_Times_Bestsellers_22_Apr_2012_New_York_Times_Best_Sellers
There are millions of books available free at the Internet Archive ( http://www.archive.org/ ), Project Gutenberg ( http://www.gutenberg.org ) and other sites:
http://slodive.com/design/top-websites-to-read-download-free-ebooks/
As for sourcing the digitized books, there is a growing community of 'scanners' who are using inexpensive homebuilt gear and simple free software to scan books. Here's a peek at their world:
http://www.diybookscanner.org/

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