problems canceling my MLBTV.com Monthly subscription

I purchased a monthly subscription to MLBTV.com Premium, to watch live baseball games, etc., through the MLB At Bat App on the iTunes store. After downloading the App, a second purchase of the monthly streaming was required for MLBTV.com. I can't find help in canceling this monthly subscription, and when I try to call iTunes, there isn't an option.

MLBTV.com isn't showing up on my Apps in my App purchases, or as a TV show. How do I do this?

Thanks