For character modeling I agree with jay. Start from a cube, and slowly refine the mesh from there.
But for car modeling, I find the edge extrusion method to work better for me. But that's just me. There are a million and one ways to model any particular model. It's finding the best, and most efficient method for you that's the trick. I would try following a tutorial for your first car, adapt to that artist's methods, mimic them, and then follow other tutorials, and do the same. Eventually you will know most of the tools you need, and so, you can begin to hone your own methods.... before long you will be able to throw a model together without the assistance of tutorials. But never abandon tutorials even when you think your good enough at a certain thing (modeling for instance) even the pros watch tutorials. Mostly for method purposes. To see how other good artists achieve their results. And maybe incorporate new methods into your own work flow.
Personally I would start with the car model, as they generally are easier to accomplish (to a degree) than organic/character models. With cars the topology is relatively straight forward. It should consist of Horizontal, and vertical edge loops.(mostly)
where as when organic modeling the topology will become allot more complicated, as you try to replicate the many forms of the an organic shape, such as a human.
There will be direction changes in the edge flow, and you will have to put allot of foresight into your model. predicting good edge flow for animation/deformation purposes. And topology is something you will have to learn too, or at least learn to predict it, manipulate it, and use it to your advantage.
My first model was a spider. I made it in Blender. I then Downloaded the Maya 7 PLE and followed a tutorial to model a Locomotive. I then modeled a Dragon by myself. I was pretty impressed with the results at the time. 
Anyway, good luck, and most importantly... Have fun!
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Last edited by Mayaniac; 06-09-2008 at 02:12 PM.
