Originally Posted by somms

For my '11 370z with the sports package, I put on 18x8.5 Enkei Tuning Raijin wheels, with 225/50R-18 Michelin X-Ice Xi3 XL tires. The wheels look and perform great, and the tires are still good after eight winters.

You want a smaller width during the winter so that your tires dig instead of skate. I also put 25mm rear and 15mm front spacers on so that the wheels don't look so sunk in, but that's just a cosmetic choice, it doesn't affect performance.

Edit: Tirerack will be able to tell you what equipment will fit based on your make/model/VIN. Maybe you can translate that to the used market, maybe not.