If you go to the website and click it says the speakers' bureau is sponsored by and lists a number of groups like Amnesty-Ineternational and churches, etc..but you'd have to get a copy of their IRS filing to get the full details. My hunch is Saudi and pro-Saddam folks, but it started in 1998 obviously to fight sanctions so their may be some money there from elsewhere as well (French maybe). It smells.
The first mention I find of his speech here is by a blogger on July 16, 2003 in response to an article by Kevin Drum in The Washington Monthly (foremerly edited by Matt Cooper. oddly enough.)http://www.washingtonmonthly.com/archives/individual/2003_07/001661.php#018818
Honor the Legacy was initiated by U.S. war veterans and the Education for Peace in Iraq Center (EPIC). The coalition also includes: Amnesty International USA, Oxfam America, the National Council of Churches of Christ, Physicians for Social Responsibility and Veterans for Common Sense.
This seems to refer specifically to the cosponsors of their Honor the Legacy program, but it's probably a good indicator of where their general funding originates. Several of the groups I see mentioned there were part of the Cold War CPUSA front funding network--the National of Council of Churches/World Council of Churches was one of their chief fundraising sources, along with some charities like the Rockefeller Foundation, the Ford Foundation, the Stern Family Fund, the Rubin Foundation, etc. (for a more detailed list see the appendix to S. Stephen Powell, Covert Cadre). This network is now interlinked with the "Shadow Party" funding network largely subsidized through Soros, Peter Lewis, Jane Fonda, and Stephen Bing (I say "through" because they may be conduits for funds originating elsewhere).