Thanks, I'll use google too. But since I've seen many fans on dA, I was wondering if they could tip me on the biggest and most widely used ones. On dA I've found one group called HeartofJapan, but maybe you know some others?
Depends on what you mean by "japan-lovers". If you're looking for platforms mainly related to manga and anime (and games), there are plenty out there. If you're looking for a less otaku-ish experience, there's also a few websites (one of which I used to visit a few times, but forgot its name plus it was in German...) out there.
And by Japan-lovers I mean fans of Japan, people who are very interested in Japanese culture (including Japanese popular culture), who go as far as to create fanart and fanfiction and maybe even dress Japanese (or cosplay) and dream about visiting or living in Japan.
I guess mainly platforms for manga and anime, since Japanese popular culture is what creates most Japanophiles/Japan-fans, right? But those less otaku-ish websites also sound interesting: are they as popular as these manga and anime inspired platforms?