Last weekend I shot indoor seminar video inside a hotel conference room. There was only regular room lighting set up, no extra or natural lights. I used DVX100B to tape the speakers' presentation. Because of the PowerPoint presentation, the room light was dimmed to minimum degree and make speakers' faces look extremely dark. My supervisor asked me to get two extra continuing video lighting in next seminars. I'm novice to continuing video lighting. What kind of light should I get to get my job done ? I will avoid high temperature in front of speakers. Some said to go for fluorescents light.... I really have no idea.
The stage is 20 feet wide and my DVX100B is seting up 50 feet away from the podium. I plan to put two continuing video lighting with stands 45 degree in front of speakers but I don't know how much power I need. Do I need a diffuser ?
For an amateur project, what's the minimium entrance fee ?

Many thanks.