What’s the best way to model a vehicle?
by deciding that a cube is a sufficently reasonable vehicle.
your question is so vauge that it’s impossible to answer. Are you trying to do an existing vehicle [like a honda civic?]? can you find the blueprints? do you know how to use the modeling tools in blender already? What kind of detail are you hoping for? millions of polygons and nurbs modeling? subsurf? polgyon modeling? thousands of triangles? Hundreds of triangles? tens of triangles?
Hey man. I was wondering this myself, and then finally tried to make one. For trucks, I’d suggest block modelling. Use a cube and extrude and make cuts to add more vertices. There’s a good tutorial on WikiBooks.com but I can’t remember what the article is called. It teaches how to box model a porche. Good luck.
I would start with learning blender.