booking thru AAA really doesn't have anything to do with magic bands.
you'll want to go onto the disney world website and create a my disney experience account and link your reservation.
there you can customize your magic bands.
you can only choose from solid colors which are red, orange, yellow, green, blue, pink, and gray.(if you want ones with designs on them you'll have to buy one when you get there at an additional price for about $26. you can also purchase things to decorate it such as sleeves, sliders, and charms)
its one size fits all with a piece you can remove which will make it smaller for those with smaller wrists.
you can customize the name that you want to appear on the inside of each person's magic band.
you can use your real name or a nickname. for example i have 3 and the first time i put "figment" the second time i put "Dee" and the third time i put "Deanne".
if you want them shipped to your house you must provide a shipping address.
otherwise you can opt to receive them at check in but if you want to do online check in and use them for disney's magical express then you'll want them shipped to your house.
you have until 30 days prior to your arrival date to customize them and they will ship shortly after that.
most people receive them between 14-21 days prior.
if you do not receive them in that time frame you may want to contact disney.