You can try to search for key words like "names people died 9 11" using your favourite search engine. CNN has a memorial webpage which has all the names you're looking for, even the age they had, nationality, etc.
Google What are the names of the people who died on September 11. Then click on the CNN website Memorial September 11. The names are listed in alphabetical order. They are also pictures of some of the victims. It is very moving.
Put the phrase "World Trade Center deaths" into a major search engine and you will find one of several sites that give complete lists of those in the buildings, as well as those in all four planes that were crashed and those killed at the Pentagon.