Just go slowly, you can try it for two weeks. You may cave in and eat something that is not veggie, but it takes time and do not put pressure on yourself, it is a lifestyle change. I would get some books and read up on it. You have to educate yourself.
Where do you live? You can always find restruants and shops that are for vegetarian/ vegan.
Good luck and dont give up. If you fall just get back up, and do not listen to the negative, listen to how your body is feeling ( I sound like a hippie )