Hi. Generally speaking, for non pickups VW's and Mercedes' seem to be the favorites. I think the ideal car for biodiesel, is the Jetta Station Wagon from 2003 (or between 2000 and 05). Beautiful car, high mpg.
But for pickups, the choices are limited. There are small diesel pickups from Toyota and Nissan and others, but are rare in this country. I opted for a VW Rabbit Pickup from the 80's. These are readily available. Try ebaymotors or craisgslist. A good one should cost between $4000 and 8000. I love mine. I've had no trouble stemming from the biodiesel.
Their advantage is extremely high mpg (about 45) and easy conversion to biodiesel by exchanging the fuel lines with Viton hoses. They can use biodiesel without the hoses switched, but the hoses will degrade eventually. Make sure you get one that is an original diesel engine version. I made the mistake of buying a gas to diesel converted one, which means nothing is according to factory specs and the mechanics are often bewildered. Disadvantages: small cab, two seater, hard suspension, loud motor, etc.
See my blog to see how many other mistakes I made (and fun I had), etc. It also explains the difference between biodiesel and WVO/SVO. http://biodieselcaddy.blogspot.com/
I don't know where in CT you are, but in NY there is tri state biodiesel where you can just fuel up. I haven't tried them, but they seem to be a very professional outfit.
Fueling stations in the US: http://www.biodiesel.org/buyingbiodiesel/retailfuelingsites/biomaps/biomaps.shtm#
or try craigslist for smaller retailers.