If you're looking for his email or phone number, you're going to have a bit of a hard time, sorry to say..
Celebrities don't just give out their personal contact info. If you really search hard enough, you're probably going to find someone who will trade you for it. (I highly suggest, going and trying yourself)
Good luck :)

Dear People,

How can I contact Clint Eastwood himself - want to write him something and can't find any valid or real email address / facebook page / phone number.

Looking forward Very very much on to your answers,

Thank you:)!