The information on the conference is here I would drop them a line, though the program itself has some excellent speakers, there may be space. I'm just going to listen and network.
There's also a conference the day before that one:

The Petrocollapse Conference
All Souls Unitarian Church
16th and Harvard Streets, NW, Washington D.C.
Columbia Heights Metro Station
May 6, 2006 9 am - 7 pm
http://www.petrocollapse.org/

I'm getting piqued.