"I was just totting up my Amazon buying experiences (UK, US, CA, FR, DE & JP) so far, the other day and marvelling at how easy it was, [...]"
Bought a CD from Amazon Japan - not cheap but not available in the UK. Their only shipping option for anything was courier - not cheap. When it arrived it fortunately was just under the UK Customs threshold. Otherwise the courier's paperwork informed me that they would have charged me £50 for clearing it and collecting the fee.
I never buy anything expensive from the USA for the same reason - even ordinary post can incur a Royal Mail "collection" fee of double figures. There's also the risk of a USA Amazon Partner labelling it as a "gift" at a much reduced value - and it's you who is then in trouble with HMRC for a false declaration.
Buying a DVD from Amazon France cost a small fortune in delivery charges - and it wasn't express either.