OP mentions live play as 'tournaments'. For tournaments, you usually have to sign up somewhat in advance. Watch who else is signing up and try to strike a conversation with them. Once you have 'met' a few of the players. it makes the trip to your table a little less un-nerving, even if who you met is not seated at your table right then.
You can also approach many tourney players and tell them it's the first time you've played AT THAT CASINO or ROOM. Ask if there is anything you should be aware of. It's not admitting you've never played live before, just that THIS place is new to you. Helps break the ice.
For ring play, watch the tables for a while, especially the one you might want to join. Watch to see who the 'friendlier' players seem to be and when you get seated, make sure they are one of the ones you look at and greet when you sit down. Gets them on your good side from the start, in most cases. You can also spend a few minutes and talk to someone from the sign-up desk or pit. Same question there - "anything you should know?"
Having said even a few words before sitting to play helps clear the cobwebs and gets the butterflies flying in some sort of formation.
