Building a gaming PC

Hi everyone, I'm from Portugal and I saw this video which show us how to build a gaming computer for 400$ or arround that, but the thing is, since I don't have alot of knowledge about computer parts and things like that I'm not sure if it's right for what I want, and I can't spend alot of money, only arround 400€, and getting computer parts from amazon or other shops that have a high cost shiping for Portugal will cost me alot more then it should because of the shiping...

I wanted a computer that could handle Guild wars 2, it dosen't have to be in the max, but something that could handle the game in medium or something like that, since it's one of the games that I play most at the moment, as long as it could run anygame, even if it was in minimum it would be good, not sure if possible with only 400€.

Thanks for the help everyone :)

maybe you should look for some portuguese online shops who sell pc hardware?
take a look at this build i put together on (only portuguese online shop that I know of) 

Sorry I took a while to awnser, thanks alot for your comment, and do you think that with this pc I could run Guild Wars 2 with no problems? :)

Oh, isn't the graphic card missing?

Thanks alot ^^

that AMD A8-6600K has an integrated GPU...
here is a test on that processor, where they also did some benchmarks with guild wars 2..

you could also get the A10-6800K, which has a bit more GPU power...

Oh, I see, thanks m8 :D Must get the money now :P I should be getting it by christmas time ;)
Thanks alot :)