The truthful response is most likely what you've already heard. Japanese people vary as much as people in any other country, and you're going to find every type of person here. There is no answer that is going to be sufficient for all, most, or even some experiences.
That being said, you're (again, like other countries), going to get the most variations in answers based on "regularity" - that is, how present are foreigners (and skin color, etc.) in that area? Tokyo? There's a "million" foreigners, no one will give you (or any other person) a second look.
If you are like I was, in a town of 10,000 where you were literally the only non-Japanese person in the town, yea, you're going to get more attention (positive, negative, and everything in between).
Speaking to cultural norms, I'd say that Japanese people will, *on average* be less likely to share their opinions (positive, negative, etc.) compared to some Western countries, so you are less likely to *see* their thoughts about you, regardless of what they are thinking.
This has absolutely nothing to do with foreigners, though, and more simply a way in which the culture approaches the sharing of opinions and thoughts.
