10 months ago
Last edited at 6:08PM on 2/19/2013
You buy a computer case, motherboard, processor, power supply,hard drive, cd/dvd drive and an operating system from someplace like newegg.com. You install the processor on to the motherboard, then install the motherboard into the case. The hard drive and cd/dvd drives are screwed into the case and attached to the motherboard via the wires that come with them. The power supply is also screwed into the case and the electrical wires are fed to the drives and the motherboard.You connect a monitor, keyboard and mouse to the new computer and then boot it up with the operating system cd already in the cd drive. From that point on you follow the prompts on the screen to install and configure the operating system. Voila, you have a computer. Congratulations
You buy the parts. CPU and motherboard. A video card/GPU is often a part of the CPU or motherboard now days so you don't have to buy those unless you want a better one. If you're building a computer to play games, you'll want to get a separate one. Then some RAM. A case. A power supply, but sometimes cases have power supplies in them, but again you need to get one that covers the power needed for the CPU, motherboard, and video card. A hard drive. Then you put it together.
Roger Anglin kind of stole my answer with going to Fry's Electronics. The last time I wandered around in that place, I noted a lot of computer making equipment for sale there. Of course, it may help to live in California because I have no idea if Fry's Electronics has stores in other states. It may also help to know how to put the pieces together, even though they might all be available at your local Fry's electronics. But I understand it is not as difficult as most people would imagine. Still, I don't know how. (I barely know how to USE one, much less build one.)