The only way to get an AAA discount on a package is to book them through AAA. If you're having a hard time finding a good agent, just ask around. Or ask at the office closest to you who might be a Disney Specialist or for someone that LOVES to sell Disney. That should get you started!
I booked our package through AAA and saved about $200. I went to the main AAA website, and got re-routed to the MidAtlantic site (which you might be in since you're in PA) and then filled out an online request in the Disney section. I had an email response the next day. The TA that I had (Kathleen) was great...though I know I bugged the heck out of her with my "well if I did this..." and "what about adding this..." She's earned her commission off of our sale, that's for sure!