How do I find a missing relative?

I have looked for my father for over 30 years...My mother married her in 1963 in Chicago; she was 30 at the time and my father was 25. He worked for the U.S. Postal Service on the West Side of Chicago in the 1960s and stayed in the Sears YMCA when he and my mother broke up,circa July, 1964. He was born in Nillister, Texas and the only thing my mother told me that he had a sister named Judy. He umed the name, Edward Teuex (pronounced Two X) when he converted from his Baptist faith to Islamic practice. Upon talking to the minister, some 15 years ago, to my dismay, because of his age at the time, he couldn't recall too much about marrying the two of them at a church located on Roosevelt and Pulaski in Chicago. I would like to know about his side of the family; I was the only child borne from their union, although I had 3 other brothers from other fathers.