The [Borel seminar][1], which is the classic reference for equivariant (Borel) cohomology, containins a wealth of information and is quite readable.


  [1]: http://books.google.co.uk/books?id=yqbocEpFdyQC&dq=isbn%3A0691090947&ei=Ak0PT6aWA5-KzAT6w7DeAw&redir_esc=y