I'm in Nagoya. I recently bought a 35L from B&H and had it shipped directly to Japan and it worked out to about 4000 yen on a 9man lens... So it seems it is just the normal, current, sales tax of 5%.
for those of you wondering, the 35L sells for about $1700 USD... hence why i picked it up in the u.s. for the cheap cheap price of $1200.
9 man is quite cheap for that lens. B&H has it listed for $1,379 (plus tax, and after instant rebate). Sounds like you got a good deal, in any case.
Here in Australia, we have a 10%GST (same as VAT), however, if I buy something for my business, and I do need to take photos of my products to send to customers and put them up on my website, then I get the GST back.
In the US we have tax deductions instead; if you buy something whose primary
use is for business, then instead of getting the sales tax back, we get to subtract the cost of the item from our taxable income (so it's as if we never made that money in the first place). Depending on how rich you are that could be a bigger savings than sales tax, but there's potential legal liability involved if you declare items like that for a self-run business, so it's not really as big a loophole as it sounds.
If you now consider that there is indeed a VAT in most US states (the range is from 0% to 13% according to Wikipedia), we Europeans might indeed not be that bad off, but for some reason one of the US guys can probably explain much better, consumers are usually not charged VAT when buying goods online or across state borders.
It's super complicated! The one thing that's true everywhere is that for most consumer goods, the tax is not included in the sticker price (which I believe needs to change...), but aside from that there are a lot of differences, because taxes can be set at both the state and county levels, which is even more complicated because the states are federated while the counties are devolved!
In California, New York, and most of the other densely populated places in the US have a sales tax rate between 8% and 9%. 0% sales tax only exists in five states and is mostly a ploy to get people to come live there; they have higher other taxes (primarily property tax) to make up the lost income.
However, the rules for when sales tax is charged are also very complicated. Some items are immune to sales tax, like unprocessed groceries (fruits, vegetables, some meats, etc.). Most items are taxed, but if you purchase from out of state then even taxed items are sometimes not taxable. Usually it has to do with some "place of business" legal clauses. If you buy an item in the store, it is taxed, but if you have it shipped to another state, then it is only taxed if the destination address is a state in which the company selling it does business. So for example, I can order an item from B&H or Amazon and pay no sales tax, but if I order from Newegg or Canon I do pay normal taxes. This is problematic because it gives certain companies (read: Amazon) an enormous advantage on the sales of high-value items, since people in many states can save about 9% by buying there instead of in their local camera store. This is a big contributor to why all the local stores are going or gone out of business.
Whew, that was more than I intended to write.