I'm sure this has probably been noted before, but ask your doctor's office for their old magazines.

I asked my dentist's receptionist what they do with the old magazines. I left with quite a variety, and a box big enough to fill two to three flat rate boxes! 

Ha! I'm always a little nervous about the mags at my docs office. You know... all those *sick people* have touched them. lol

Our libraries and the auto supply stores also have expired magazines.