Someday students seeking a college loan might go to a Web site, fill out a brief questionnaire, and get connected to the lender with the best possible rate. Such a system would bring cheer to students seeking straight answers, lenders seeking fair competition, and colleges seeking relief from investigations led by Attorney General Andrew M. Cuomo of New York into their murky ties to the loan industry. Yet months of expert attempts still have not given students a true loan-comparison Web site, as their creators confront an array of technological, political, and competitive hurdles. This article outlines the obstacles facing such ventures.