Where can I get my camera upgraded?

Bought a 10 megapixel nikon today but want it upgraded. Where can I go or do?

You can't upgrade a camera. You upgrade by buying a better camera.

If you want more megapixels, that is no reason to buy a new camera! Check in the cameras menu and see if you are operating your camera at the maximum megapixels. Also make sure your ISO is set to something reasonable like ISO 200 for out doors. And last but not least spend $4.00 and have an 11x14 print made (full frame) of one of your better shots. For reasonable price processors, I use costco.
So I say to you that if you are judging the quality of your camera by 4x6 size prints, you are not getting enough information to make an informed decision. Also the people who develop your prints may not be up to snuff!

You never mentioned what camera you bought today, nor what reason you want a better camera. As was mentioned you don't up grade, you buy a new one. Without knowing what you don't like about the 10 megapixel Nikon no one can help you.