I have used Small World Vacations (my TA has always been Stephanie and she's great) with great success. I also booked one trip through AAA because of a discount I could only get through them - my TA was great, but some have said that AAA TA's who are not very familiar with Disney can sometimes be less than stellar, though a lot depends on how complicated a request you have, I guess.
We have had great experiences with Small World Vacations (WDWVacations.com) that we found on mousesaver.com.
The problem with AAA is that they are a full service travel agent. You may end up working with someone who knows little about WDW. All the Small World agents are Disney "specialists".