You will find Vancouver to be VERY vegetarian friendly, no matter where you
go. But here are a few recommendations:
Fast food: Yves Cuisine on 4th Avenue (take-out food made with the popular
Yves meat replacements)
Krishna on Davie Street -- zero atmosphere, yummy Indian buffet. And very
cheap! I'm a student, so I eat there often.
Casual: The Naam -- bad service, great food. All vegetarian, with many
vegan selections. Menu is very casual, burgers, pizza, veggie cutlets, etc.
Best miso gravy in the world!
Nice: Anna Purna on 4th -- Incredible all-vegetarian Indian food
Nyala on 4th -- My favourite little restaurant. Awesome Ethiopian food!!!
Not exclusively vegetarian, but has an extensive veggie selection. I think
they have a website at www.nyala.com.
Fine dining (very expensive): La Lumiere -- not a vegetarian restaurant, but
has a set vegetarian multi-course dinner which I hear is amazing.
There is also a Buddhist restaurant in Chinatown whose name escapes me that
I've heard good things about.
You will find pretty much all restaurants in Vancouver to be accommodating
to vegetarians. As for the low-fat, well, you just have to be picky, like
in any restaurant.
Hope that helps!