Cain A.J. and W.B. Provine (1992). Genes and ecology in history. In: R.J. Berry, T.J. Crawford and G.M. Hewitt (eds). Genes in Ecology. Blackwell Scientific: Oxford. (Provides a good historical background)
Conner, J.K. and Hartl, D. L. "A Primer of Ecological Genetics". Sinauer Associates, Inc.; Sunderland, Mass. (2004) Provides basic and intermediate level processes and methods.