Mike - Here's a small list to get you started:
Walter Reed Society, Inc.
Walter Reed Society. They handle much of the charitable relations for the Medical Center. They may also be able to get you in contact with the Walter Reed Auxiliary, which also helps with charitable functions, including social events.
Walter Reed Public Affairs Office 202-782-7177. They would handle any media inqueries, and may be able to put you in contact with someone that will be able to help get this started.
Keep us up on anything related to this. I'd imagine I could take some time out to help...