Can you help? Where is he?

I am trying to find my father Avelino Ramirez Almaguer. His birthday is 08/30/58. He is 48 soon to be 49. He is hispanic/mexican and I think he might be in Durant, Oklahoma. I would love any tips on how to search for him free. I've tried 411 and others like it, but he is not listed in any yellow or white pages. I would appreciate any tips on how to do criminal, marriage, or divorce searches. I cannot afford to pay for searches or investigators so any help is greatly appreciated. God Bless~