ROLLED FONDANT QUESTION???? HOW TO MAKE HOMEMADE FONDANT?

The best recipe for rolled fondant is to use a tbs of glycerin. I don't have any and I do not know where to get it except for on line. I have to have this cake made by tomorrow and have no time to order it. can I leave out the glycerin and still have the fondant turn out ok? is there a substitute i can use? can i add more geletin?