Shane, S. (2003). A General Theory of Entrepreneurship: The Individual-opportunity Nexus, Cheltenham: Edward Elgar; Timmons, J. A. and Spinelly, S. (2004). New venture creation, New York, McGraw-Hill.
Above books will give you insight into the theory of entrepreneurship. Following one may be used as a classroom textbook. Hisrich, R. D. and Peters, M. (6th Edition) Mcgraw-Hill