I'm trying to find information about the ideals, lifestyle, and practices of the Order of Assassins, but a lot of what I'm turning up seems to be completely biased. Any good sources I should turn to?
I'm a British historian, so they aren't my specialty, but I did a project on the Assassins for an undergraduate seminar. Here's some of the highlights from my bibliography to get you started-
Bartlett, W.B. The Assassins; The Story of Medieval Islam’s Secret Sect. United Kingdom: Sutton Publishing Ltd, 2001
Daftary, Farhad. The Assassin Legends; Myths of the Isma’ilis. New York: I.B Tauris & Co. Ltd. Publishers, 2001
Lewis, Bernard. “The Sources for the History of the Syrian Assassins.” Speculum, Vol. 27, No. 4 (Oct, 1952), pp. 475-489
Nowell, Charles E. “The Old Man of the Mountain”. Speculum, Vol. 22, No. 4 (Oct, 1947), pp. 497-519
Wood, Juliette. “The Old Man of the Mountain in Medieval Folklore”. Folklore, Vol. 99, No 1 (1988), pp78-87
Imad ad-Din, Ibn al-Athir, and Manaqib Rashid ad-Din.“The Assassination of Conrad of Montferrat.” in Arab Historians of the Crusades. Trans, Francesco Gabrieli. University of California Press: Los Angeles, 1969
Daftary is a large name who has written extensively on the topic, I recommend searching for some of his other works.
In terms of the issue of bias in your sources, this is something you're going to have to work through. The "Assassins" were a group which was widely misunderstood by both Christians and Muslims at the time, and also very quickly passed into the realm of mythology (Wood covers this). Unfortunately, most if not all of the primary sources we have for them are through the perspectives of outsiders.
Its a very fascinating topic though, and definitely something I would love to have the chance to return to someday. Best of luck in your research!
I asked a similar question from a poster on here a little while back with a great list of books, none of which I've had time to read unfortunately. For the sake of completeness I'll provide a link to the original discussion below and you can see if it's of any value to you.