If you're skilled enough and there's a trustworthy store near you, you could buy single components and build up your own pc. Parts for a low-end pc would cost 250-300 Euro (case, cpu, mobo, cooler, ram, hd, gpu, dvd-rom) - of course it depends on the performance you prefer.
In case you prefer a custom built pc choose dell or get a mac mini. (I would take the mac mini, which comes with MacOS X. Dell terrorizes its customers with Windows XP Home Edition ... scary!)
