I read The Believer when I can get it, in hope I'll come across a Nick Hornby written article eventually.
I also read arty magazines you find at Borders which are expensive but contain a bunch of new cutting edge artists who are interviewed and you can see photos of their works. I have one issue of Empty (the all pictures issue), the very first issue of Dangerous Ink, which publishes readable online versions of their magazine but the first issue is always a good buy for collector's value. I also have Acclaim, the street art and culture magazine which is about urban design.
I used to have some Men's Health magazines in my youth, which were helpful in understanding what my body was going through *blushes*
Generally I buy magazines I find interesting or helpful. I also have a few Big Issue Australia magazines.