Students with disabilities are guaranteed access to assistive technologies (AT) by provisions of the Individuals with Disabilities Education Improvement Act (IDEIA) (2004) and its predecessor, the Technology Related Assistance Act (Tech Act) (1988). Design and development of AT, including devices and software programs, has burgeoned to a point where availability and affordability are no longer barriers to access in schools. However, research has reported that lack of teacher expertise continues to be a significant barrier to effective access to AT and that models and strategies for improving teacher expertise are desperately needed. This study involved evaluation of preservice teachers' knowledge of, and comfort with, using AT and integrating a prototype computer-based DVD--Encyclopedia of Assistive Technology (EAT)--into instruction. The EAT includes innovative video based tutorials that guide viewers through the operation of AT devices and software programs. Results of pre- and post-measures indicated significant increases in comfort with AT following use of the EAT, and the results of the study, as well as teacher candidates' satisfaction with the video based tutorials, suggest it is a viable model for enhancing teacher expertise with AT.