To find eBook in FTP Search, visit one of this website
http://search.ftphost.net/
http://www.filesearching.com/
http://reliz.ru/
http://www.narlytime.com/
http://amun.serveftp.com/
http://ftpsearch.tomsk.net/
e.g. if you want to search " Sams Teach Yourself " just type Teach Yourself, you will have some eBooks in some FTP servers.
also can be found with specific format (e.g. PDF & CHM)