They'll fit fine. My favourite thing is an often overlooked detail by a lot of people that buy aftermarket wheels, they don't buy hubcentric rings - and you won't need them with any of the OEM wheels. Always check the sizes of the wheels, there is a lug in the rear wheels that idiot-proofs them and prevents them from being mounted on the front axle. You don't want to get home and find out youve got two wheels you can't use.
I highly recommend the forged track wheels made by Rays Wheels if you can score a set, think of them as budget Volks. There was someone selling a set in 350Z Classifieds a while ago. The V1s are in a size where you can get appropriately sized summer, all-season and winter tires for them, the V2 Tracks are limited to summer tires only - but those wheels loom amazing.
350Z Wheel Identification Guide
I just noticed I need to fix the pics in this article I did a while back, but it's got the specs for all of the OEM wheels for the 350Z.
Good luck on the shopping!