It all depends. if you know about computer a lot, then build yours. I'm going to build mine over christmas break. if you dont have knowledge about computer then you can buy it from and place to buy on from. cyberpowerpc.com is a good place to buy it. also, i would like to say that you spend about 200$ more dollars on a prebuilt pc than when you built it yourself. i suggest go and reseach build guides on youtube and spend about 1-2 hours looking on how to build a computer. not only do you save money, but you know how you built it and what you put in it. my specs go as follows for my build. it is no more than 1000$. AMD FX 6300(CPU): 120$,
GIGABYTE GA-78LMT-USB3 AM3+ AMD 760G USB 3.0 HDMI Micro ATX AMD Motherboard: 70$, nvidia EVGA GTX 760: 250$, ADATA XPG v 1.0 RAM 8GB: 80$, Kingston 120 gb ssd( just to hold the windows. 2x faster than a HDD) 80$: 70$, Western Digital HDD 1 tb (for storage like pics and videos for rendering if doing youtube), Bitfenix Prodigy M case: 100 $, and the EVGA 600w PSU. There you go a total cost for me all together with tax and shipping is 1010.92. but you dont need a SSD, you can just have HDD it is much cheaper but way slower. for the money, it is worth getting what i have. it ca run minecraft shader 40 -50 FPS. (i benched it.)