Would someone help me to know what are the sites which provide the service of making users able to read free Chinese books online?

龍騰世紀書庫
http://www.millionbook.net/

has most of the classics and contemporary classics.

Thank you very much for your reply , i have opened the site but it seems to be in traditional chinese , and in fact i am studying simplified chinese, so would you tell me other sites in simpilified chinese ?
Thanks in advance

There are websites that can convert traditional characters to simplified ones

For a start, try google translate's URL translation function