I’ve just been called racist. I’m fairly sure I’m not. All I said was I find blondes and redheads of fair complexion attractive.

It's not racist to be more attracted to one group over another as long as you don't discriminate. For example, if you have a blonde and a brunette apply for the same job, and the brunette is more qualified, but you hire the blonde because you find her more attractive, that would be discriminatory.