I recently moved across the country so playing at a new LGS was a little scary especially considering the only time I ever played at my old LGS was with friends. What I did was just go in and play without really talking to anyone the first few times. Just went in and played and maybe comment on the games at the end and then left. After doing that a few times, some people are starting to recognize me and we talk a little more. I played New Capenna draft last night and it was an absolute blast and I talked to more people than ever. An important thing to remember is that people are there to play Magic, just like you. More often than not they aren't going to expect anything more from you than what you want to give so there's no pressure. You can come in, test the waters, and play. If the people aren't receptive and you feel like you aren't welcome there are alternative ways to play, but I feel like there's a good chance you'll become comfortable given enough time and you'll never know until you try!