Dearborn is supposedly the most Arab and muslim 'city' in the US (pop 100k, not much of a city). It's only 40% arab, and some percent of that group are Lebanese Christians (the earliest Arab immigrants to the area). Suppose there are some non-arab muslims though. I can't seem to find decent religious demographics in a quick search.
Canada has been sending a few anglo islam converts to go die in arabia lately. I have no idea what would inspire someone who grew up in Calgary or Winnipeg and got a proper first world education to go martyr themselves for Allah in the third world, but nonetheless it does happen on occasion. The amount is so minuscule it's lost in the noise though.
I suppose the same deal happens in the US on occasion.