For anyone to even reply to that you need to be abit more upfront about what your asking. Whats your budget? are you starting from scratch? and so forth.
Yea, what Lasrix said.
However, if you want a sturdy, good computer for about any use, for about $800 (more if you want better, but you won't need it) I can give you some good links (for the whole computer)
Thats pretty hard to come by for 600 bux if your starting with absolutely no parts. I think its probably doable tho. I could do the reasearch on it but im too lazy.. And that probably would not include a monitor.