Sorry I gotta call misinformation on this.
I've been vegan (no animal products whatsoever for ethical reasons) since 1996. I have never had any problems with lack of nutrients and I don't supplement at all. I just eat a health, varied diet. Its based on fresh fruits and vegetables, whole grains, nuts etc. I generally dont eat junk food or fast food.
The only two things you need to make sure is in your diet on a very regular basis is iron and b12. Dark green leaf vegetables for iron and soy milk for b12 works for me. Protein is a non-issue. If you educate yourself you'll be fine. Dont let the fear-mongering get to you. The FDA has approved the vegetarian diet as safe and actually recommends it because its much lower in refined sugars and cholesteral. Its much healthier if you are your responsible.
You'll get alot of flack on the veg choice, but stick to your guns. It has to come from the heart otherwise its very hard to keep to it. Nobody can force you to do it.
Google for the Vegetarian Resources Group.
Also "Diet for A New America" by John Robbins is a great book that I recommend for sound advice on nutrition and the positive effects a veg diet has on your health, the environment and its benefits to other humans.
Good luck with it!
Edit: Here's a pic of me to prove I am not an anemic dwarfed out nerd!