I agree with the Starbucks suggestion. Either a gift card for coffee or a gift pack would be nice, and should fit the price range request. They have them in all the stores. The CD is also a good idea. It's a bit difficult to buy gifts for people you don't know well outside of work.
I just put together a Christmas Tin of goodies. DH didn't want to brave shopping, lol. I put a cd, some chocolates, almond rochas, homemade chocolates in a Christmas Tin and baked my yummy Pumpkin Bread. Coworker is well taken care of I think.