If you have a Batteries Plus near you, it's a good place to look for a variety of batteries you'd usually assume could only be found at Radio Shack. I was surprised to see lots of the little button cells which I need for a variety of devices, like Photon Lights. I believe many cost less than the "one price for any cell (whether you usually need 1 or 4 at a time)" garbage Radio Shack has been pulling.
Additionally, they conveniently repacked an odd cordless phone battery for me when no Radio Shack could find a replacement to order from their catalog. That's a pretty useful service, and it cost me about the same as a replacement battery, had I been able to find one.