I'd like to second what Dale said. Preachy vegetarians just end up getting smacked by those who aren't. It accomplishes nothing, I'm not a pastor and there ain't no way I'm going to try and "convert" people.
I do, however, speak my mind when someone asks or speaks ignorantly about being vegetarian. Then, and ONLY then, will I get a bit more... "vocal"
I'd like to touch on a few other factors:
- Again with protiens, Omega 3 and 6 from Flax are very complete, and a dietician will validate that, so again - go see them if you're at all concerned.
- Be open to trying weird, weird stuff. My wife *HATED* tofu when she "joined the fold", but now she loves it. Try everything once, if you've had Sushi I'm there is little in vegetarian meals that will make you raise an eyebrow... except for Vegan cheese. My girls love it, I won't touch it with a 20 foot pole.
- It is INSANELY easy to buy veggie now. Safeway, Save-on, Superstore, etc - all of these stores have either sections, or in the case of Superstore, an entire line of vegetarian products (Superstore's PC Veggie Chilli is AWESOME)
- Look into ethnic dishes. You'll find huge selection of Indian cuisine, Mexican, Thai, etc. Lots of tastiness!