Ford Edge key

Here is my situation. My wife slipped on the ice at Walmart last night (Im gonna deal with them this morning), unfortunately her keys fell out of her purse and we cant find the key which is the one with the remote in it. So I need to know where to get another one at, where do I take it to get it cut and can I buy instructions on how to reprogram it. Also, the one I have left for some reason stopped opening and closing the doors on the remote. Could it be the battery? Can i replace the batteries and will it work again? Please help. thanks.

well i found the key at customer service at walmart. however, my personal key doesnt activate the doors remotes, my wife's found keys do. so how can i check to see if the batteries are low, how do i take this apart? it would be cheaper for the battery replacement instead of the reprogramming. thanks

I dont have an Edge or any car that new, but most of those remotes can be pried open by twisting a dime in the grooves at one edge. The battery may or may not be low, but I would buy a new battery of the same 'number' anyway.
And you should ask the dealer, and at a locksmiths, to see what it takes to get another key to work with your car. It can be expensive, so you might want to know about it. The owners manuals used to have some instructions about changing batteries in remotes.
Good Luck. I like cars old enough to have simple metal keys - but usually I have to tow them home, rebuild the engines/transmissions - in order to be able to rely on them for daily drivers.