First off, be glad you are in the USA. It's a bit more difficult to eat as a vegetarian/vegan while shopping at a commissary in Germany. I've only found one store here that caters to us, and it is closed on Sundays. I am not much of a cook, so when I switched, I bought lots of cookbooks and spent countless hours finding recipes online. I only use ones with pictures so I know what the final product should look like :P After that, I bought a binder and have been compiling recipes that come out good. After a year, I have an entire cabinet dedicated to every spice known to man, and nutritional yeast is my best friend (provides B12). Always keep some bananas in your fridge (takes longer for them to ripen, but they don't attract fruit flies while they do). I use to do bulk shopping every other week and never used a list, but I had to learn to go weekly and go with a plan, because produce doesn't stay fresh for long and it kept going bad before I would use it.

It's surprisingly not that difficult. Beans, rice, pasta, and potatoes make for easy and filling meals that can be varied with different vegetables, condiments etc. Taco Bell and Chipotle, while not the healthiest, are definitely your friends when you're out or don't have a lot of time. Salads and cereal with almond milk are almost no prep, smoothies are an easy way to load up on fruits and greens, and it's always a good idea to have plenty of fresh fruits and veggies on hand for snacks. You really don't need to worry about any deficiencies if you're eating a good balance of grains, beans, fruits, vegetables, nuts and seeds, except maybe consider supplementing B12. It takes some getting used to, but I've never felt better, and the risk of all kinds of disease drastically decreases. forksoverknives.com engine2diet.com and nutritionfacts.org are also great resources. Good luck!