Not as such, no, not the kind of instructions you're after if it's a first time build, but there are a lot of online guides. There are also magazines you can buy with how-to guides.
http://www.pcmech.com/byopc/ http://www.buildyourown.org.uk/pc-information/ http://www.mysuperpc.com/
See also http://forums.hexus.net/hexus-hardwa...500-600-a.html