http://www.amazon.com/Building-Customer-Specific-Retail-Enterprise/dp/0967256208/ref=pd_bbs_sr_2?ie=UTF8&s=books&qid=1215629168&sr=8-2
http://www.amazon.com/Customer-Intelligence-Gary-Hawkins/dp/0967256216/ref=pd_bxgy_b_img_b