I have received the latest volume of this excellent book published by CQ Roll Call. This covers the 113th Congress and includes biographical details of every member of Congress and details of election results. I have been buying Politics in America since the 2002 version (107th Congress) and used both my own copies and earlier volumes whilst in Washington for background research on the individuals who had been (or are) whips.
It is available in the UK through Amazon (your purchase through this website will cost you the same, but contribute to "Washminster") - or from CQ Roll Call in the USA.
I also buy National Journal's "Almanac of American Politics". That is not yet available, but can be ordered at
(My order is already in).