V.P.
They have something at the Flower Mound Library called "MagShare" where you simply drop your magazines off, and they'll share them with visitors. There are also bins sorted that you can take magazines whenever you'd like as well. I'm not sure if they Sanger library has a similar system.
I also ask friends. Simply bring a stack of magazines with you the next time you meet for playgroup or dinner, and I"m sure you'll get some takers.