Yes. And not often. They're always used as translation of English "white people" and "black people". In fact, to make a distinction of black and white is rather a western thing. Race can be very obscure and the only time we have to make that distinction is when we learn history. Foreigners are just foreigners in Japanese minds. I also happened to know that, in US census, they ask you what category of race you fall into. If I remember correctly, they have black, white, Hispanic, Asian, and others. I don't think a lot of Japanese people have that kind of mind frame. It might seem the idea that "Obama is black because Americans said so" is a little bit far-fetched but it has that element. It also brings up the question of "he's partially white. So why is he black anyway?" I won't delve much further into this but you know...

In private conversation, yes. Not to their faces though.

Though 100 percent Japanese, I was born and raised in the U.S. Even though I celebrate oshogatsu, eat gohan with natto, I am a gaijin (foreigner)

I had a double take on that. I'd say it's not really that gaikokujin is mainly used for Asian foreigners. It's just that Asian foreigners account for a huge percentage and they're often indistinguishable from Japanese by the looks, resulting in being called out less by the colloquial form "gaijin".

yes. hakujin : white people kokujin: black people gaijin: used for non-Asian foreigners gaikokujin: mainly used for Asian foreigners