A shopping follow up in case anyone else with the same problem reads this thread:
I had trouble finding a USB extension cord at Office Depot, Staples, and Radio Shack. They have them but not with the right connections at the ends. Be sure you look for one that says A/A , A to A , or A Male to A Female. What the stores here stock were almost all A/B which is what you want to connect a camera or a printer to a USB port on a computer. One salesman sold me an A/B and a separate B/A adapter, but the keyboard didn't like that, no response. I ended up ordering the right cable from an online company -- Cables to Go -- for much less $$ than any of the cables at a retail store.