I cracked the screen of my touch screen nikon coolpix camera

Contact a Nikon certified service centre and ask what the replacement of the screen cost. Then look what a new camera costs and decide.
If you still can make pictures, but you can't see the results, go on shooting and try to live wit the broken screen. Take care from a broken screen sometimes dangerous fluids can leak out. Don't touch the chemicals, wipe them off with a paper towel.

If it looks like a crack, it is a crack. You may not feel it because the internal screen is protected by an outer screen. Pressure of some type is usually the cause of cracked screens. This is an expensive repair.

http://imaging.nikon.com/products/imaging/lineup/digitalcamera/coolpix/life/l20/index.htm

The above is the web page for your camera at nikon.com.

http://www.nikonusa.com/Service-And-Support/Service-And-Repair.page

The above tells you how to get service and repair at Nikon.com.

Check this one: http://www.ownta.com/nikon-coolpix-s230-digital-camera-repairing-lcd-display-screen-replacement-with-touch-screen.html

heey, i also did this to my camera and i dont know what to do with it. and also the bad thing is, you can't even use it if the screen is broken! which is really a pain. sorry i can't help you, but maybe send it back to nikon.

Here it is: http://www.ownta.com/nikon-coolpix-s550-digital-camera-repairing-lcd-screen-for-replacement.html

This is your need: http://www.ownta.com/nikon-coolpix-s51-digital-camera-repairing-lcd-display-screen-replacement.html

You'd better buy a opening tool together if you want to fix by yourself.

Google the words...disassemble a digital camera.

i think your touch screen is gone because it might have fallen so  it had the crack. 

I will buy it from you.