Is it possible to contact a famous musician or celebrity by email?

I produce songs as my hobby.I've already done 10 songs with some famous singers who live in my country(Sri Lanka).And I'm very interested in producing songs to international artists.So I tried hard to contact 1 of them.But counldn't.I sent messages from their official websites.But didn't get any replies.So I really want to know a way of contacting them.Hope y'all will help me.