To begin with, here is a quick overview from Japan Guide:
http://www.japan-guide.com/e/e2127.html
For more information (and pictures of the samurai), go to this art history site:
http://www.artelino.com/articles/samurai.asp
This site is more comprehensive and will eventually include a scholarly journal:
http://www.samurai-archives.com/
But if you are just interested in the history of the samurai, go to this page. It is part of a site on Judo:
http://www.judoinfo.com/samurai.htm
The samurai lived by a code, which was called Bushido or the way of the warrior:
http://mcel.pacificu.edu/as/students/bushido/bindex.html
For more detailed information, see this reprint of the first chapter of Bushido: The Soul of Japan (1905). Note that its author, Inazo Nitobe, is also engaged in clearing up Western misconceptions about Japanese culture:
http://www.sacred-texts.com/shi/bsd/bsd06.htm
The Samurai have figured in popular culture, particularly in film. One of Kurosawa's most celebrated films was The Seven Samurai, which was later remade as The Magnificent Seven.
For more information about Kurosawa's film, see these pages:
http://www.imdb.com/title/tt0047478/
http://www.culturevulture.net/movies/SevenSamurai.htm
http://rogerebert.suntimes.com/apps/pbcs.dll/article?AID=%2F20010819%2FREVIEW...
The Magnificent Seven itself has been remade, but here is a link to the 1960 movie starring Steve McQueen & other 1960s action greats:
http://www.imdb.com/title/tt0054047/
Other films about samurai include Kurosawa's Kagemusha, The Twilight Samurai, and The Last Samurai.
http://www.metalasylum.com/ragingbull/movies/kagemusha.html
http://www.kfccinema.com/reviews/swordplay/twilightsamurai/twilightsamurai.html
http://lastsamurai.warnerbros.com/html_index.php
Not surprisingly, samurai have also figured in anime.
http://www.umich.edu/~anime/genres_samurai.html
http://animemoon.moonmage.net/kenshin.html
http://www.anime-source.com/banzai/modules.php?name=Anime&rop=showcontent&id=785
