Builditsolar.com is a great site for teachers who want to get their students interested and working on solar projects. It also has a list of sites that teach ordinary people how to conserve water and energy, to make biofuels, water pumping, etc.
Journeytoforever.org has lots of step-by-step instructions for all sorts of different projects. Here is the beginning of one of them on biofuels:
(1) Start with the process, NOT with the processor. The processor comes later.
(2) Start with fresh unused oil, NOT with waste vegetable oil (WVO), that also comes later.
(3) Start by making a small, 1-litre test batch of biodiesel using fresh new oil. You can use a spare blender, or, better, make a simple Test-batch mini-processor.
Continue reading at the site itself.