Katja; want me to come build one for you?

A good place to start might be with computerland.nl, they have a shop right next to Den Haag CS, nice place, good service and they do assembly for you, so you just kind walk in, say what you want then come back a few days later.

EDIT: Also, might I say, with 4000 euros, the sky is the limit, infact, I would go so far as to say its too much, you don't need much more than 1200 for a very nice system with TFT and such, but 2000 will deffinatly get you something that will last and last and last.

Contact me if you want more info, I used to build systems for P&O Nedlloyd......much more fun building modded systems.