For anyone looking for the magazines while at WDW, in addition to World of Disney at Downtown Disney, the Animation store at the exit of the Animation attraction in the Studios usually has them. I've seen them in AK as well, in the Discovery Island shop to the RIGHT as you approach the Tree of Life. I've also seen them at the Main Street Cinema in the MK, but not as frequently as the first two places I mentioned. Art of Disney at Epcot probably stocks them as well. Obviously, the closer it is to the release of a particular issue, the more likely it is they will be in stock at these locations.
If World Of Disney (or any of these stores) is out, they can look up on the computer anyplace in the entire resort that might have them. This was helpful to me once, as one of the magazines I was looking for was sold out at World of Disney and in the parks, but still available at a few of the resort gift shops. I ended up getting it at Coronado Springs.
I've since found out Barnes and Noble carries the magazines, so now it's less urgent for me to find them at WDW!
I have every issue so far and really enjoy them!
BTW, managers at any gift shop, including in the parks, can tell you where anything is located anywhere in the resort, if they have the product number (I think its called a "SKU number" or something like that). I've tracked down books, t-shirts, and plush I was looking for this way, when the particular store I was in was out of what I wanted.