Ty M, Find links below 1st link is the service repair manual and 2nd link is possible replacement generic screen which you can also do a search on for possible better pricing. Good luck. I hope this helped you out, if so let me know by pressing the helpful button.
http://tim.id.au/laptops/hp/compaq%20evo%20n400c%20n410c.pdf
http://www.sears.com/search=HP%20%20Compaq%20Evo%20N400c%20LAPTOP%20LCD%2012.1%20Screen%20