Do I need to warm up your automobile before driving it?

No!  Cars today are built with the expectation that you will be starting them up and start moving.  There are some expectations when these would be necessary, but generally people know if they have a vehicle like that.  Some turbo diesel engines need to be warmed up so they can properly operate.  Also motorcycles generally are warmed up because they are high-performance and therefore driving them hard immediately after starting them can damage the engine.  However, it will not effect the fuel economy, besides a lot of motorcycles are getting 50 miles to the gallon, more or less, so a few minutes idling would not be the same as letting your V-8 sit for 5 minutes to get warm.