where is the websites thats inform about free ebook?

try this one: www.free-ebooks.net

I don't know and it's wonderful for me too if there are sites in the net for free e-book.

Here is a great site for free ebooks - http://www.heygidday.com/download.htm There are 1,000s on this site and there is no fee. You can even sell them if you want. The site was started by an acquaintance of mine from Australia. He used to sell ebooks; but, now he makes his money other ways. So, he set this site up and shares all the ebooks he has collected for free. Enjoy.

I know only two places: one is in spanish, called Libros en Red, quite good, actually, and tha other one is Project Gutenberg. But I bet that if you type "free e-books" in any search engine you will find plenty!