Photoshop College Project Help

So I'm in the business program at my school, for my marketing class I have to design and market a new product. So I'm going to make a "car company", and i need to photoshop an suv, sedan, and a truck (which will all be laid out) Im just wondering if anyone have any big pointers on rendering the cars in photoshop? I know photoshop pretty well, but any advice or tutorials from anyone would be greatly appreciated!

Thanks guys.

made this tutorial for someone a while back that might help you.

the red area is your selection area



then you switch to the move tool and bring the selection area down

from there, you crop out the copied area at the top, level out the body with the wheels, etc etc.

google digimods. i believe its www.digimods.uk but i havent been there in some time. another name is the photoshop bible.
very good websites that take you through the basics, and some advance stuff