will these work on the g37s?
Offset: 45mm Backspacing: 6.29" Bolt Pattern: 5-114
Link

I'm looking for the cheapest wheels I can find... really didn't want to get new rims just for winter --> I live in NJ, it doesn't snow enough to warrant it IMHO.

 

IMO using the stock rims for winter is not a good idea, you'll get scratches from hard snow and in a couple of seasons your tires will be damaged and your rims scratched due to mounting-dismounting the tires, low profile tires are difficult to mount-dismount. I got 225/50-18 Blizzaks and Sport Edition A7 from tirerack but they just listed the rims "Sold out for the season" maybe you can try find them somewhere else, those were the cheapest I could find and they turn out to fit perfectly. The link you are providing is a search for a 2008 G35 Sedan? You have to take into account not only the offset but the shape (curvature) of the spokes too, there might be two different rims with the same offset and one clears the brakes and the other doesn't.

 

Found a set of 18" OE wheels off a 2008 G35s.

Width 7.5J
Bolt: 5 x 114.3
Offset: 45

Since it's off a 2008 G35s, I'm guessing the offset would be fine, should be a perfect fit, right?