The odd thing is that I can only check this from my PC at work and my Mac at home, both of which are within a few miles of each other here in the British Channel Islands. Before you ask I'm not sure if the changes even correlate to the two computers, I really think they are random and they aren't that frequent either. It does tend to stay at the right price most of the time. The only other thing I can think of is if the IP routing protocols might sometimes be connecting me via somewhere further away so it looks like I'm in a different location - clutching at straws here though!
Well, this is rather surprising--it's priced at $9.99!
(Rachel's Shoe by Peter Lihou)
I'm sorry; I confused you with ambiguous wording. You earlier were upset that overseas customers were being charged more than the price you were advertising. I suggested that you could avoid turning them off by saying it was $9.99 (higher outside the US because of taxes and wireless charges) or some such wording.
Pete, it doesn't keep changing. Outside the US, there's a surcharge for VAT if any and Amazon's extra cost for wireless delivery. When they made their deal with Sprint in 2007, the carrier had a huge surplus of capacity, so Amazon no doubt got a great deal. Such deals aren't available in the UK etc. (I am stunned to discover that if I use the iPhone in Europe, I pay $1.99 a minute for what in the US is free or--if I use Virgin Mobile prepaid wireless--18 cents a minute. Gives a whole new slant to the notion of roaming in the gloaming by the bonnie banks of Clyde!) There's probably also an allowance in there for the cost of exchanging money, which tends to run 2 or 3 percent plus a fee of 30 cents or so (PayPal rates).
A US customer will always see $9.99, a UK customer will see a higher figure, and customers from elsewhere may see something else entirely, but it's consistent for any one country. Perhaps it would be less confusing if Amazon priced in the local currency, but it doesn't and isn't likely to.
It does actually change within a country (as far as the customer is concerned) because I've seen it change between two prices whilst within the same VAT free jurisdiction over here. That was the only reason I posted this enquiry.
However, Kindle hasn't really taken off here in the same way as the US so I'm pretty relaxed about the situation if my selling price in the US is $9.99.