Preparing for Civil Services in the USA

I am preparing for civil services examination. The problem is I am in the US and currently working for the State of Missouri (Missouri Department of Natural Resources). The fact is, I am always fascinated by the UPSC and this is my last attempt. I need help regarding books/notes/coaching material on Psychology and Sociology. I would like to interact/co-ordinate with students having these optionals. I would like to join the group of students who are preparing for civil services with Sociology and Pyschology as their optional? I am visiting India (Jawahar Book Depot) in July first week. But definately, I will appreciate a co-operation/wise words from teh veterans of this mother of all exam.
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