Although I have AAA, I find myself forgetting to take advantage of the various discounts available.
While the discounts are not always the "best" prices available for things, they do allow you to get a discount for things you already intend to purchase or use. Let's say you plan to stay in Hotel A in City Y, don't forget to ask for the AAA discount.
In my experience, the best bets for discounts are:
1. Hotel Rooms
2. Amusement Parks
3. Airport Parking