I like brunettes but I do have a crush on a guy who has blonde hair, but when I met him he was brunette (and for a short amount of time bright pink!). I like hair on the darker side. Basing that mainly on I don't think I've had a crush on someone with blonde hair before.
I think that a natural hair color is the best. Because I think it's weird when a guy changes his hair color as much as a girl celebrity. It's so tacky and fake. I wouldn't not like a guy because of his hair color, it's not like it was his choice, but if he changes like nuts, it's crazy. (exp: bleach blond, sick)