I was looking at something the other day that wanted to charge taxes etc when you bought it. The price wasn't that high though and came under the limits so I thought it might have been a con and didn't buy!
"If you buy goods online from outside the EU for delivery to the UK, you'll have to pay Customs Duty (if over £120 value) and Import VAT (if over £18) on top of the purchase price, though Customs Duty is waived if the amount of the calculated duty payable is £7 or less."
Those amounts wouldn't be so bad in most cases except that on top of that you have the couriers who usually charge you £8 or so for collecting the charges! Shysters!!