The following websites offer information on diseases (zoonoses) that can be contracted from animals by humans.
University of Pennsylvania
County Of Los Angeles - Department of Health Services, Public Health Programs and Services - Disease Control Programs, Veterinary Public Health and Rabies Control Manual - Overview of Zoonoses
World Health Organization - Zoonoses and Veterinary Public Health (VPH)
University of Wisconsin - Madison - School of Veterinary Medicine, Zoonotic Diseases Tutorial