Need help building budget system

I don't have much information about what I need other then I have a 300-400$ budget, this is for my brother and he just lost his job but needs a computer for general use, microsoft office, surfing the internet and thats it. I wanted to just get him some kind of dual core amd system because they arent expensive.. I know hardware is very cheap right now but I want to make sure I get the right parts that wont break down any time soon. Can someone help me find something really cheap? Thanks. if I did something wrong in this post i'm sorry.

he just needs a pc with no monitor, something I might be able to throw a few upgrades in to it so in the future it wont be too slow to do general stuff. Mabey start with 2 gigs of memory. I just don't know where to go for the best prices..

thank you

(I am new at building computers, I know how to do everything but I just wanted to make sure that the parts are compatible and are easy to work with, where I wont have to spend forever trying to get things to work..)


I would like to have this system within the next week, he has a 17 ' lcd at 1280x1024, I don't care what brand as long as its durable, I dont need a keyboard and mouse,