Update: in some stores the flyers w/ the code are behind the register so if you just ask the barrista about the new macchiato or if they are free he/she will grab a flyer & enter the code. This was at the Starbucks in Latham.
Check your local Starbucks for these flyers:
"Indulge in a free Tall Hazelnut or Carmel Macchiato. Our special treat to you.
Offer valid between 3/5/2013 and 3/31/2013. TRY THEM HOT OR ICED BARISTA: PLEASE RING AS DISCOUNT CODE 350."
If your store doesn't have the flyers or is unaware of the promo it may
work to just give the barista the discount code above. yymv