Many people I encounter and eat with aren't used to vegetarianism and how do I handle them when they look at me funny when I can't order the meat at the BBQ place, for example?
Vegetarianism is a choice and many people don't understand it. You can appeal to them and say that it is your choice and they aren't affected by it in anyway, so they should stop worrying so much about other peoples' lives.
When some of my friends wonder about or insult my vegetarianism, I usually just shrug it off and say, "Yup, I don't eat meat anymore. So what?" And that's usually the end of it. Sometimes, I'll tell them that if they have questions about it, I'm happy to answer them, but I'm not going to force them to avoid meat when I'm around and I won't make them feel bad about it.
You can also check out No Meat Athlete Radio a podcast where they sometimes talk about the Vegetarian/Vegan community and how they deal with "aggressive" meat-eaters who think we're all just a bunch of idiots.