I've been looking around and can't seem to find a aftermarket spoiler for 06 4dr sedan. I find universal spoilers but I don't know the exact size I would need. Also don't want one that 10 inches in height. any suggestions???

Try using keywords like "g35 sedan spoiler" and look through photos until something catches your eye.

I think the keywords you're using aren't giving the results you want, also make sure to switch your search page to images only.

I've used key words like G35 sedan aftermarket spoiler and g35 sedan spoiler. When I click on images all I can find are the lips sadly. I feel like they don't make spoilers custom for the sedan. That's why I was wondering the size that I would need so I could just a universal GT wing.

Get a tape measure, cut out some cardboard, and figure out what size looks good to you.