A study gathered information about producers and distributors of unabridged books on cassette tape for the use of librarians engaged in collection development. Questionnaires were distributed to 48 public libraries and 45 producers/distributors. This report includes an introduction covering the history of this medium and a rationale for collecting books on cassette in the public library; a literature review; a description of the survey methodology and results; and a discussion of the findings. A two-part directory to producers/distributors based on the survey results is then presented. The first part provides the results of the producer/distributor survey questionnaire, including the addresses and telephone numbers of the respondents, information on the number and genres of available titles, and policies on discounts, damage, duplication, ordering, and shipping charges. The second part reports librarians' comments on each producer/distributor. Copies of the questionnaires and additional names, addresses, and formats for producer/distributors are appended. (48 references) (MES)