GoNuts- if yours is a simple rectangular glass sheet, you can order same from any decent glass shop. You need the exact dimensions including thickness, and the glass shop will need a few days to send it out to get it tempered or they have the tempered outfit cut & temper it. I did that recently on a rental remodel where the renter broke the shower door; door had two round holes for special hinges. I had to supply an exact series of dimensions (which were slightly non-rectangular & included whet to center the holes). A simple rectangular sheet should be a breeze & cost maybe $100.
Baja-tested '08 2-slide 36'
Alpine: The Ultimate DIY'er Project