Use the following publications to find industry ratios (remember you need your company's SIC and NAICS codes).
Industry Norms and Key Business Ratios: Located on the table behind the reference desk. Call number #HF5681.R25 I525 (this is the easiest one to use, so I recommend using this one). Find your industry by SIC code.
RMA Statement Studies: Reference books in the reference room.
Almanac of business and industrial financial ratios: Located same as above books. Call number #HF5681.R25 A45.