Wellll.....
Sopisco News : Newsletter entirely dedicated to the banana and reefer shipping industry. has some of the latest news from its newsletter, and they're now offering free trial subscriptions to the newsletter.
Other than that, if you read Spanish,
the Publications section of the Ecuadorian Banana Export Association is pretty useful and has lots of stuff about commercialization of Ecuadorian bananas. In particular, the magazine "Bananotas" is excellent.
Generally, I just go to the big Haciendas and ask at the front desk if I need information, but then again I have the advantage of living in Ecuador.
Hope this helps!