I don't think that hardware is cheaper in Europe but here you go:
Germany increases its VAT by 3% to 19% on January 1st, so buy sooner if you can.
Two shops from Munich were recommended to me on IRC, you may browse them to have an idea how much hardware costs there:
Litec Computer and
NB-Computer.
The prices include VAT and a 1 year warranty (by law, in the entire EU and Switzerland) but normally no shipping costs.
If you buy stuff for more than a few ?100, it might be worth to jump the administrative hoops to get your VAT back. You have to prove that you leave the seller's country and you need a form signed by the seller. You will then have to pay the VAT of your state which is likely a good chunk below 19%. Search the customs office of your host country and the US for further informations.
// And if you buy hardware that isn't powered by USB or FireWire, make sure it works with 110V/60 Hz current, too.