There are some GREAT vegetarian recipe sites out there that will help you organize meals and supply yourself with the protein you DEFINITELY need. I personally love vegweb.com, even though I'm not a full-blown vegetarian. I really love a lot of their recipes! Also, try a product called Quorn as your meat substitute... I found it in the organic/health food section of my grocery store and you cook it straight from the freezer bag in the skillet. Tastes delicious and has a much firmer texture (more like chicken pieces almost) than tofu.
Be careful with soy products if you happen to have thyroid issues as soy inhibits absorption of thyroid med.
Protein is an essential part of your diet and if you are skipping meat then you should try something like tofu or similar non vegetarian protein food to aid in your weight loss. Not only protein can curb your hunger but also can help you build muscles ( if you are working out) to burn more calories.
Most of the same rules for dieting apply. You just need to ensure you are eating a balanced diet and that you are getting the right nutrients. If you go to the Healthy Cooking Forum you will find lots of good recipes - many of them vegetarian and on the health pages there is some information about dealing with cravings and issues around vegetarianism and how to lighten up your cooking. Do ensure you are getting sufficient protein through beans and dairy. Good luck and do join our weight loss challenge.