I'm not sure giving your address is a problem; it's a public information. What bothers me is the doxxing; I don't want my online identities to be easily linkable to my actual name. (But if you want to make an exception for me, I could make an exception for you: write me a DM ;-) .)

There groups that will help you find people ;)

I've heard of TypePals.com that offers a repository of people wanting to exchange typewritten letters, and that seems cool!