everyone started out from nothing. remember that. you don't put your stats in your profile, but it's easy enough to see that you're not exactly huge.
well - neither was I. neither was my partner, for that matter. he bought a gym membership and drove over to the gym every day for 2 weeks before he had the nerve to walk in.
sure, there will probably be some assholes there that will look at you with contempt - but it's THEIR problem, not yours. You will find that there will also be guys - probably in better shape than the assholes - who will encourage you and respect your honest efforts at working out.
if you can afford a week or two with a trainer, that will help you over the hump and give you a short list of exercises which you can do with confidence while you explore the other equipment the place offers.
please - get to the gym, and get some assistance getting started. you'll save time, you'll get better results, and you'll feel better about yourself for having done it.