Any advice on selling magazines?

Me personally, I would put an ad out on the web, letting people know what you have, how much, and the condition of the magazines. And you could also try selling them individually or as a group. Also, look up special issues on Yahoo! (Yahoo, you're welcome) or on the National Geographic website, and keep those issues separate and DEFINITELY sell them on their own. There are collectors everywhere, and I'm sure there's a guy, or girl, looking for a specific magazine for their collection.