The above links to SVO/WVO folks are good. I think one that gets overlooked a lot is:
www.biofuels.ca
This is neoteric biofuels, and they've got a few nice products. I'm almost ready to begin my own conversion. Phreetogo's suggestion regarding Dana Linscott's site is a really good one too. He's a great contributor on the other grease boards.
good luck with the conversion!!
Kevin