If the battery is dead, it doesn't need to be reprogrammed. New batt will fix it.
It's pretty rare that a remote just dies. Usually people go to the dealer because they need a spare, or because their remote just died*.
*....they dropped it in water. Take the one you have apart. It should just be four peices- two plastic outer bits, the button pad, and a circuit board. Look for moisture, of course, but also for corrosion, especially under the rubber buttons. Those little interlocking traces are what actually trigger a signal to be sent. There's a conductive material (graphite?) on the underside of the rubber buttons to connect the split circuit.
I encountered some GM's with repeated remote failures that turned out to be bad pads. It was prevalent enough that you could buy just the rubber bit off of eBay to fix your remote. My test for this was putting a battery in the bare circuit board, and 'shorting' (not really shorting, just completing a circuit) the little button contacts with a small screwdriver. If that worked, I knew it was the pad. What actually went wrong with those, I have no idea.
Also:
1) If it does need a new one, see if you can buy one off the internet and/or if used remotes can be reprogrammed (some makes sell new ones with a code...you input the code to program it, and the remote is then locked to that vehicle. Can't be reprogrammed to a diff vehicle, even with the code).
2) Ask what the labor is at the dealer, and if that changes if you provide your own remote. An hour is typical, even though it takes minutes. If they're nice, a half-hour (40-60 bucks depending on the dealer).
This isn't one of those dumb remotes with a non-removable key blank sticking out, is it?
edit: oh, also, check and be sure you can't program it yourself. Some makes/models have shortcuts that will allow a strange series of actions to sync the remote. I remember Nissan/Infiniti having this for their older/cheaper remotes (not keyless drive). Something about lots of ignition switch turning and locking/unlocking. I could never even find instructions in the factory literature...I was just cool with the guy next to me, and he would generally just say 'give it to me' and do a bunch of shit really quick, and boom, programmed.