Definitely outlets if you want to be sure they are authentic. Ebay is wonderful though, and sometimes cheaper than the outlet and sometimes not, depending on the demand of the bag on Ebay. If you buy off ebay, definitely post in the authenticate this thread.
JAX is the central warehouse for coach, it's in jacksonville florida
here is the number for customer service
1 888 602-6224
just give them a style # and they can look it up
good luck!!! it's worth a try depending on what your looking for