I have been on Veggiedate.org, Veggiefishing.com, and spiritualsingles.com, on and off over the last seven years. I went traveling for a good part of that time though. But here's what I discovered.
Veggiedate.org has a lot of very OLD postings from women, and a lot of new ones too. Their search functions are quite good now, although they weren't when I first joined. it's a hassle to sort through them all, find one that seems great, then notice that she hasn't even logged in in three years ! I think a lot of women vegetarians are very idealistic, and rather uncompromising about what they want from a man - someone to bankroll their wildlife rescue farm or such pipe dreams - unrealistic expectations need an outlet, and this seems like the perfect place...
Veggiefishing is less search-friendly, but also FREE. FREE means that more people post who aren't serious about finding someone to build a relationship with. I haven't had much experience with it, but it seems to have some potential- lots of members at least.
Spiritual Singles has given me the finds that I have actually dated. It is frustrating though, because I can't sort for vegetarians AND for key words. And many women there hit on me and are NOT vegetarians. I have concluded that people become "spiritualized" shortly after becoming traumatized. I saw some very serious PTS going on with these women. But I have also found some VERY INTERESTING artists/ musicians on here. I currently have two women interested in me from this database.
I just wish someone would start a service for single vegetarians in the performing arts.
Mind you, I live in a large metropolitan area, where this kind of database is bound to have some close matches... Best of luck to you. Being firm about wanting a vegetarian partner ( or at least primarily vegetarian) makes perfect logical sense- but try not to extend yourself into thinking this is the mine where to find the perfect gem that you dreamed about as a Disney-hypnotized child...that's really part of our society's oppression tactics... keep people separated and weak by making them think they have to wait for perfection to show up. Remember the song Desperado by the Eagles, and you will do well.