It's not what you're asking, but I really suggest simply looking for online friends through a language exchange or something. There's something really creepy about looking to meet people of another specific nationality. If a Japanese came up to you and said they wanted to be friends with an American, you'd probably think it was exciting. But would you feel the same way if a Somalian or a Croatian did the same (for example, I'm thinking of unfashionable nationalities)? It must be a little weird for Japanese staying in America, being approached by novice anime language studiers and white otaku. It's really kind of weird. Look for people who want to meet foreign people, and online is the most normal way to do it.
Good luck!