Two computer data bases have been developed by the Computer Science Department at the University of Western Ontario for "Information London," the local community information center. One system, called LONDON, permits Boolean searches of a file of 5,000 records describing human service agencies in the London area. The second system, called INDEX, consists of the same information classified into 45 subject-oriented files. Users retrieve a file by subject keyword and browse through it. Online retrieval using the two computer-based files and manual searching using the telephone directory were compared in an experiment carried out by students at the UWO School of Library and Information Science. Systems were evaluated on the basis of answers to a set of 16 questions, both with respect to the time taken to obtain a correct answer and the number of satisfactory or correct answers produced. Four analyses of variance were applied to the data obtained: effect of question order on proportion of correct answers, comparison of the three systems in terms of time to reach satisfactory answers, time to reach an answer when location of the information in the data base was known, and proportion of questions correctly answered. Results indicate that the greatest potential for the computer lies in the production of agency lists and updated manual indexes rather than in direct online retrieval. (Author/JPF)