I hope you know how to solder...
try these sites:
http://www.instructables.com/id/Replace-the-top-screen-of-a-Nintendo-DS-without-o/
http://www.youtube.com/watch?v=2BJmhXZZ_j0
http://site.powergamingparts.com/RepairNdsl.html
Wish you luck (I'm in much the same position)
Shell
December 2007