its all about what you want from it. Are you a core gamer or a video editor if not then keep it under 1500.
Also another important question. Do not bother looking up items and doing research less you have the cash on hand. Computer hardware changes so often that you must simply buy the best bang for your buck and have no regrets.
A common misconception is that it is cheaper the build your own computer then buy one. Yes that was once true but now it is more or less the same price to build as to buy. So unless you just want to say you build your own computer consider buying one.
What you buy will highly depend what you want to use the computer for. In case you need it for gaming, you might require high speed processors, graphic cards, RAM, Motherboard, strong mother board, and all the computer accessories that you can not make. Visit the site http://www.kitchentablecomputers.com/index.php for more details.