Cecil tried to answer the question on where that “new car smell” comes from:
http://www.straightdope.com/classics/a990528.html
I believe this question is answered in one of Dave Feldman’s “Imponderables” books. (Right or wrong, I don’t know.) He may not have anything past Cecil’s first paragraph, though.
New car smell can be bought.
A friend of mine sells used cars. He has a spray he puts in them once he has cleaned them entirely that makes them smell ‘new’.
I couldn’t find the product on the internet, but I found this site for a similar product, from a different manufacturer.