when will you have replacement glass for iPhone 4

Joshua,

When you are looking for the rear panel glass, please keep in mind that the glass attaches to a frame that is similar in design (not the same frame of course) as the iTouch front panel. It is plastic and somewhat difficult to go through the process of mounting the glass to the frame. We would recommend finding the entire assembly for the rear cover versus the frame and glass panel separately. If you have further questions, feel free to drop us an email at mipodrepair@hotmail.com

Well the best thing that you can do is to get it from an authorized Apple spare parts dealer and get it fixed with the help of a professional iPhone repairer. Don't try to replace the screen on your own, as one needs to have steady hands and a good experience in order to get this thing done, else you might damage it even further.

make sure you buy the original glass screen. here is an info graphic on how to tell the difference between copy and fake.