And most of you are missing out on it!
Especially the US companies. Many seem to try, but they say things like, "We ship internationally, to the US and Canada", or they give the telephone number "1-800-xxx-xxxx" which does work in Canada and a few other countries outside the US - but not most! Many don't even go that far. 'US only' is the most common thing I see. It's not just the US, other countries do the same. Believe me, if you've got a really good product, I'll be happy to buy it even if your company is on the moon.
There are lots of good sites out there that are, and should be, local. Pizza delivery places, for instance. I certainly wouldn't want a pizza delivered from Sydney to Florida - it would be a touch too cold by the time it got here - and I'd be very hungry. I went looking, a bit over a year ago, for places that ship home-style foods (at the time I was living in Thailand and a bit homesick for certain foods). Nada, nothing, zilch. I found a number of wholesale food export/import places, but nothing that would ship a homesick expat some local delicacies (or disgusting foods, depending on ones tastes). I've recently found one that ships to homesick British expats (they even have haggis and marmite), and a few US gourmet food companies that ship worldwide - but gourmet isn't quite what I was looking for.
This had been a frustration for quite some time - I'd have been quite willing to pay an online grocer to send me a care package, but it was 'US only' everywhere. And online banks are just as bad - a few say they are going international, and I found several multi-country European banks, but that's it. And banking has been internationally linked for years, why aren't they international?
Those of you who will lose the most though, are the travel companies and discount airline ticket companies. I am tempted to put up a nasty site listing all those that offer 'International flights' which can leave only from the US, or only from Australia, or UK, or wherever. If I have to leave from and return to one particular country it's not truly International, at least not in my book. I'll buy an international flight from a company that knows what the word means, please - I often want to layover in the middle somewhere, and I don't want you telling me you can't give me a stop in the middle, just because the stop isn't in your base country.
So if you say you are international, mean it! That means all the nations. If you aren't selling and shipping internationally, and you can, you are missing out on half the market if you're a US company, and way over half if you aren't. Think about it.