I heard there is a book name 'inequality'.
But I couldn't find the book.
Is there any site or book about inequalities?
What i want is collection of inequalities.
You might be talking about Inequalities by P. P. Korovkin.
I am not into inequalities. But many people who know that stuff have mentioned the book by Hardy, Littlewood and Polya as a classic: http://www.amazon.com/Inequalities-Cambridge-Mathematical-Library-Hardy/dp/0521358809