Where can i find my nikon d3100?

Where can i find my nikon d3100 serial number is 7418994

That's not a phone number you could dial. There's no reference database to look that up. There's no tracking device placed in each camera from the factory. My best guess would be on the hands of someone else who knows how to take care of the camera more properly.

The serial number is embedded in the Exif information of any pic taken by your camera. There's a program called "exiftool" that you can download for free from cNet.com. The exiftool will show the serial number of any unprocessed pic from your camera. How you find those pix is up to you.

Sure it's a D3100?

There's a website where you can enter that serial number and it comes back as a D3000.

When was it lost/stolen/mislaid?