How can I fix my refrigerator, GE, model GSS25JEMD BB?

My refrigerator and freezer are no longer getting cold, what are some of the possible causes? It is a general electric side by side and the model number is GSS25JEMD BB. I noticed the refrigerator wasn't getting as cold then this weekend the freezer went out too. I noticed a puddle of water at the base of the unit when I arrived at the house. That's when I removed all of the contents.