I think the best place to start if you're into silver and gold would be https://steemit.com/created/steemsilvergold. You can find all the latest posts from the steemsilvergold tag and then comment on them. Sometimes people will start a conversation with you. You're right though, sometimes you have to start the process as people may just not know how rewarding a conversation can be. That's probably smart to only comment on what you're interested in. Otherwise, it could come across as spammy. And we don't want any spam. We want steak!