In my 30s, I went back to do a second BA in Communications (Publishing), but didn't go the Co-op/internship route. Right out of school, I was hired into a small publishing house for 8 months, and then found a contract job at a mid-level house. After that, the job scene for publishing students was tough on the West Coast (the SFU Publishing MA program pumped out a lot of qualified folks), so I have spent the past handful of years in primarily copyediting roles that ultimately went nowhere (one company went belly-up; the other has scaled back). I don't think I made nearly enough contacts, so an internship could be a very helpful way to offer a step up, especially since my interests now lie more in online publishing, while my skills-set and contacts do not.

I currently run an online magazine that I'd love to turn into a real company some day. However, I have little "real" publishing experience and would love to get some, especially in the very competitive "lifestyle" market where age is more important. How can I convince people that I'm not over the hill at 29?

It's an interesting article. A lot of people who change careers to go into book publishing do have to do internships that are unpaid or offer a small honorarium. As long as the person is doing what they want to do, it's a good idea.