lookingforfamily on Family Tree Circles

I'm looking for my biological father. He should be about 71. All I know is his mothers name was Freda. My mothers name was Barbara Mae York. My father's name is James Fredrick Christensen but he always goes by Fred.
They were married in 1958, in Seattle, Washington. She was 19 and he was 17. They were only married for about 2 or 2 1/2 years. The last time I saw him I was 6 years old, I am now turning 53 in July. I have been trying to find him through the internet with no luck.