There are many vampire covens online. They all claim to be real. Some examples would be the blood coven and vamp coven.
There is no verifiable information about specific vampire covens in Salem, Oregon. Vampire covens are typically elements of folklore and fiction, rather than reality.
Unfortunately not all covens are online and very few covens actively advertise for new members. A quick look at Wiccan Meetups, showed nothing for Belfast, however there is an Irish Pagan Federation who would be the best people to aid you:
Since vampires aren't real, there couldn't be any "real vampire" dating sites.
No
No, there is not.
Probably yes, but they might not have known it was a vampire.
No, vampires are a myth. You will not find any real-life vampires.
There are many fan groups that act out scenarios from various genres of films. Perhaps the best known are Trekkies. Look for advertisements for such groups that you are interested in joining. If you mean groups of real vampires then there are none in Seattle or anywhere else for that matter. Vampires are purely fictional.
nio vampier are not in the world only a bat Witches come in covens. Vampires come in clutches.
Yes. There are probably many. Covens are formed in many large towns and cities all over the world.
There is no "real" vampire Peter or "real" vampire of any other kind. Vampires are a fictional construct. There is not a single human being on earth who "has no reflection in a mirror".
NO, Vampires aren't real.