The books are:
Sexual Identity on the Job: Issues and Services edited by Alan L. Ellis, Ph.D. and Ellen D.B. Riggle, Ph.D. and published by Haworth Press in 1996
A Manager's Guide to Sexual Orientation in the Workplace edited by Bob Powers and Alan Ellis and published by Routledge in 1995.
Information on each of the books can be found at the linked sites on this page.
Both books have been described as "thoughtful and useful." The first book provides a review of research focusing on sexual identity, how to manage multiple identities (e.g., latina, lesbian, woman), career concerns of gay and lesbian employees, and productivity issues. The second book offers useful tips for creating a supportive working environment for all employees and presents short biographies of gay and lesbian employees, as well as heterosexuals who have worked with lesbians and gays. Many of the stories are quite moving and have a positive effect on readers.
A third book is useful for helping employees further relate to and understand gay and lesbian concerns. That book is
A Family and Friend's Guide to Sexual Orientation edited by Bob Powers and Alan Ellis and published in 1996 by Routledge.
Best wishes in your effort to celebrate and benefit from the diversity of your organization.
Links to reviews of books
Sexual Identity on the Job
A Manager's Guide to Sexual Orientation in the Workplace
A Family and Friend's Guide to Sexual Orientation
Human Rights Campaign (HRC)