well, I can only answer for my specific case, but the way I made friends at the gym was basically people noticing that I was doing the Olympic lifts and comment

well, I can only answer for my specific case, but the way I made friends at the gym was basically people noticing that I was doing the Olympic lifts and commenting on that, plus occasionally giving random compliments/technique tips to people. By weightlifting club I mean an association centered around competitive Olympic lifting. So you train individually, but can sign up for competitions, and are generally always around competitive lifters. I've also heard CrossFit has a good community, not sure how accurate this is, however.