A little over 3 years ago, I went vegan. It actually didn't help with my weight loss since a lot of my favorite things like nuts, dried fruits and bread are vegan. The only thing that has helped me with weight loss is cutting back portions and monitoring my dietary intake. I do enjoy being vegan though.
I just bought a book called "Cinch!" which is by the co-author of "The Flat Belly Diet" and someone who used to work for Prevention magazine. I think the diet is pretty well balanced.
A good book on overall vegetarian nutrition is a book called "Becoming Vegetarian" and there is a similar "Becoming Vegan" book. Basically, getting your protein isn't hard as long as you eat a mixture of foods and limit processed foods.
If you want to become vegetarian, I'd try to limit or eliminate cheese and other dairy products. They are high calorie and really don't provide you much. Things like calcium can come from a variety of vegetables such as leafy greens.
There is also a vegetarian section of the forum, it is listed near the bottom: