I spent yesterday researching biodiesel technology and companies to invest in, and then I picked up the Reader and saw your request for information on local stations that sell it.
These links are to maps and lists of stations that sell E85 and biodiesel across the country. Click here for E85 Stations. Click here for Biodiesel stations.
I just want to say that I think the corn-based biodiesel is just setting corn farmers up for a big bust. Corn will yield 18 gallons of biodiesel per acre, while algae will produce 10,000. (Yields of common crops: click here.) I'm putting my money on algae biodiesel.