I forgot about Vincent Cassel, I like that actor. He might be too young looking to pull off Lord Raith though, granted he is a Vampire, but he is also the father of a bunch of offspring, so I picture him looking somewhat older.
For anyone wondering who it is MoSeS_ and miketh are talking about, this is Vincent Cassel:
Lord Raith has several centuries on Thomas, Lara and Harry. I would assume, however, that he looks like he's roundabout in his 50s or early 60s which would be just about the right look for a man who's the father of a 35 year old guy. Vincent was born in 1966, so he's 44. Of course, there's also make up and stuff. There's talented people in Hollywood.
Description of Lord Raith from page 142 of Blood Rites, paperback edition:
The air grew suddenly colder, as if the Almighty had flicked on the air-conditioning. A man slid out of the car. He was about six feet tall, dark of hair and pale of flesh. He was dressed in a white linen suit with a silver-grey silk shirt and Italian leather shoes. There was a scarlet gem of some kind fixed to his left earlobe, though his fine, straight hair hid it until a breeze briefly tossed the dark strands to one side. He had long, spatulate fingers, broad shoulders, the eyes of a drowsy jaguar, and he was better-looking than Thomas.
Which is fricking saying something, because Thomas is drop-dead gorgeous!