What car did Edward Cullen drive in Stephenie Meyers's books?

Answer 1

Edward Cullen drove a silver Volvo S60 R, which Stephanie Meyer's website has a link to a picture of : http://us1.webpublications.com.au/static/images/articles/i551/55133_00mg.jpg

Here's her page with a list of all the cars in her books, and most of their pictures:
http://www.stepheniemeyer.com/twilight_cullencars.html

Hope this helps!

Answer 2

Okay, the car he usually drives is his silver Volvo S60 R. BUT if you read the outtakes on her website, he takes her to prom in his Aston Martin V12 Vanquish.