Maple syrup seems to be endemic for North America. Not sure about the rest of the Europe, but I don't think it can be found in shops over here in Balkans (and maple tree itself is not uncommon).
European maple trees won't help you, either; it is only the "sugar maple", native to North America, which is capable of producing syrup. Unfortunately, even in the US, the sugar maple is getting squeezed out of its ecological niche by the (imported) Norway maple...
I have never seen it in italy or hungary either (places where I lived for >1 year), in normal shops.
It can be found at some american chains where they serve northamerican-style pancakes, but in that case it's 99% sugar+colouring+flavouring.
As for maples, there are plenty all over the world, but the cultivar from which they make syrup is in fact northamerican, those we have in the old continent would not be good for syrup extraction AFAICT
I've only ever found it in Booths, which is a fancy Whole Foods-style supermarket local to me in northern England. It's labelled with the Canadian flag and "100% pure Canadian maple syrup," but no grade. I love it on my pancakes, but now I'm worried that what I've been eating all these years isn't actually real!
Decent Maple syrup is pretty easy to come by in the UK from decent supermarkets and health food shops. It's recently gotten super expensive though - about USD $2 for 100ml. All the syrup here is graded by colour and is almost always Canadian, I didn't even think it was produced in the US.
Maple syrup is great, but in the midwest, at least, most people don't eat it; instead, they put corn syrup with maple flavoring on their pancakes. Ugh.
That's true, although in Germany I find it ridiculously expensive, like 7 EUR for a small bottle which lasts only so many pancakes. Although I like the flavor a lot, I can't afford to buy it regularly. Perhaps if I can find larger quantities and B-grade...