Case in point I think is probably the best case study book out therehttp://www.amazon.co.uk/Case-Point-Complete-Interview-Preparation/dp/0971015805/ref=pd_bbs_1/202-8127999-0045416?ie=UTF8&s=books&qid=1177605092&sr=8-1http://www.amazon.com/Case-Point-Complete-Interview-Preparation/dp/0971015821/ref=pd_bbs_sr_1/102-2460731-2312945?ie=UTF8&s=books&qid=1177605184&sr=1-1The other one is Vaulthttp://www.amazon.com/Vault-Guide-Case-Interview/dp/1581313055/ref=pd_bbs_2/102-2460731-2312945?ie=UTF8&s=books&qid=1177605413&sr=8-2