The Zpizzas in the DC metro area now offer Daiya cheese. They've been offering it for over a year now. Before Daiya, they offered soy cheese, however it still contained casein. I think they finally realized that didn't qualify it as a vegan pizza. Anyway, Daiya cheese really is the best vegan cheese out there and it tastes great!
If I'm ever craving a vegan pizza (WITH cheese), I order from zpizza. Since my order is usually so complicated (because I substitute almost everything), I order online. They have a great online ordering system. It works well but the people that work at Zpizza don't always (they sometimes don't quite get it right -- be sure to check your pizza before you carry it out).
If you like a lot of toppings, the best thing to do is order the 'Berkeley Vegan' and substitute the toppings on there for what you do want. You get more toppings for your money doing this than you would if you created your own.
My favorite thing to do is order the Berkeley Vegan and substitute the soy crumbles (I don't care for their Gardein brand crumbles since I don't like the taste of sausage), zucchini, and bell peppers for roasted red peppers, pineapples, and avocados. I keep the onions, tomatoes, and mushrooms on it. That's six toppings on a pizza! OH and be sure to substitute the marinara sauce for roasted garlic while telling them to mix some marinara in it. The sauce really makes this pizza!
Be sure to sign up for their mailing list, 'ztribe'. They offer great money saving coupons from time to time.
Update: Veg DC provided a site with a listing of all the vegan pizza offerings in the area.
