Here in Houston we have Michael's and Hobby Lobby as well. Never heard of Aaron Bros. I've had my framing done at Michael's (Travel posters...not pennants). It's not exactly cheap...even with their perpetual, always on sale, framing coupon.
I've got a 5 foot map of Manhattan neighborhoods that I've been meaning to take in...if I could just stop buying pennants, I'd have the money to frame it.