I would say that the examining The Autobiography of Malcolm X would be a good start.  Yet, I would actually start with the Epilogue as written by Alex Haley.  I think that at this point, and using this as reference, reading the narrative of Malcolm X as told in his own words through Haley would allow you to collect some very good facts about Malcolm X.  If I might also suggest a secondary source by James Cone entitled, Martin and Malcolm and America.  It gives an excellent reading of both facts surrounding Malcolm X's life and the conditions that helped to bring his philosophies into being.  I would examine this source, if you can obtain it.

Why not try the eNotes link below? The famed African-American Muslim leader (1925-1965) was born Malcom Little in Omaha, Nebraska on May 19, 1925. He later changed his name to El-Hajj Malik El-Shabazz to identify his conversion to the Muslim faith. Although despised by many white Americans as a preacher of racist hate and violence, he was hailed by many as an outspoken advocate of human rights, especially for the black populace in the United States. After resigning as the head of the Nation of Islam in 1864, he was assassinated a year later by several disgruntled members of the organization who delivered at least 16 shots into their former leader.

One thing you have to remember, is that anyone as famous as Malcolm X will have any number of things written about them, and some are more true than others, but you should be sure to check the nature of your sources as you search.  If you search online, there are a huge variety of websites and a long entry on wikipedia among other places.  If you go to print resources you will likely find more reliable types of information, but you can also find a listing of his speeches and be able to listen to him and make some decisions for yourself about his agenda, his thoughts, and his character.