Hi everyone!
I would like to create a list of spots I've known some of my penpals/epals wish to visit. The Seattle area of Washington (the state) is a great spot. I have seen many Asian communities as well as Scandinavian/Germanic areas. With the more famous universities around, it is common to attract people wanting to learn abroad. There are also some colleges that offer English classes, even for beginners. I would first suggest this website, of course.
I also believe that Los Angeles, California is a good spot. I don't know the area very well, but I have a few friends who live there. I can ask them about LA.