as jorsoft03 says, its the
import tax that really kills you. Really works out much more expensive. Found out the hard way trying to source a replacement laptop screen (my PC manufacturer in the UK was quoting me at £600 (~$1200) for the part- jokers). Got it cheap from the US, but the import tax was a nasty hit.
You can get around it (illegally) by labelling things as gifts, but if the person/company who sent it is willing to do that, they won't be at all large/official so
-no customer service/returns (which'll cost an arm and a leg in post anyway)
-Would you trust some random dude on eBay, advertising (with no pic or description) 'Q6600. Brand new' (Have you noticed how many jokers try to sell things that way?)