Hi, and welcome to the forums
Your truck model looks pretty nice. I use 3dsmax, but I've seen some maya tuts at
www.learningmaya.com
A tut I used is the Fiat 500 polymodeling tutorial, which you can see here
www.3dtotal.com. They have a whole bunch of excellent modeling tutorials. Another one I used is
http://hem.passagen.se/dh1998/3d/gto/modelling01.html. It's pretty detailed.
As for making your cars look real: good lighting with car paint materials. I believe.
Hope this helps!
