I'm 34 weeks into my second vegan pregnancy. Neither my midwife nor my back-up OB/GYN have batted an eye about my diet, probably because I stay so healthy during my pregnancies. I'm very whole-foodsy, and eat very little packaged or processed foods. The exception is soy, which I use in moderation and even then, I try to stick with, say, organic tofu instead of veggie burgers or whatever.
I have a book called Becoming Vegan which is a wonderful resource, being written by the foremost veg-specialist dieticians. There is a section on vegan pregnancy, infancy, and childhood; it's just good factual information without all the hype. There is also one called Becoming Vegetarian by the same people. I'd assume it's as good as the other.
The VRG also has some webpages on veg*n diets during pregnancy, which were also reassuring. Vegfamily.com has some articles as well.
For "supplementation" I use blackstrap molasses (appx 20% rda iron and 18% rda calcium per tbs), a b-complex, and occasionally a vegan dha capsule (not that often because I make our bread and stuff with flax seed). You probably don't have to worry about the b-complex if you eat eggs and dairy, but dha or flax is pretty important.
The only negative thing I've noticed is that I have to eat all the time. If not, I have low blood sugar symptoms like nausea, shakiness, dizzyness. It sounds worse than it is, because it's *very* mild and once I learned that eating made me feel better, I made sure I ate often enough so that didn't happen. My midwife said it's not uncommon among her pregnant moms, so maybe it's not a veg thing, but *I* didn't have that problem with my first (omni) pregnancy. I think what the problem is is that vegan foods aren't really the heavy, stick-with-you foods that omni foods are. When I added more heavy foods like nut butters, and started baking more whole wheat goodies like banana-walnut bread and pumpkin muffins, I felt *so* much better. When I'm NOT pregnant I almost never eat flour products and very little fat, so it was hard to adjust.
Also, while I'm not a fan of dairy/eggs/seafood/etc., there are companies out there (eco-fish for one) who have seafood with very little or no mercury in it. I can't remember the details, just that they are very strict about testing to make sure there are no chemicals in it, and it's probably the closest you can get to certified organic fish. I was pretty impressed with the company when I read up on it. If you do choose to continue eating fish, try the health food store and see if you can find some that is safe.
Congrats on your pregnancy!