For the sake of the discussion (and the rules, I guess xD), I won't be speaking in Serbian to the OP, but I guess I should point out to everyone else that here in Serbia, the cheapest prices are with a PC pre-built by the stores that sell them. And since I don't trust stores like that and wouldn't even if it could save my life... xD
4eyed, if you really have the cash for a new PC, build it yourself. The trivial stuff you can buy anywhere, but good GPUs, CPUs and especially power supplies can only be bought in Europe, or even better, the US. It's a costly purchase, but you'll be sure that you're getting the quality merchandise, not like the class Q crap stores sell here.
Unless, of course, you really just wanna play WoW and nothing else, then I guess it's alright xD