It's definitely a combination for me. I brewed for many years mostly on knowledge from books and Zymurgy. I didn't have much of an LHBS until I was about five years in. I brewed for about nine years before joining a club and about 14 before joining HBT. However, the knowledge I've gained from every source has been invaluable.
The books gave me my foundation. The Prodigy "Wine, Beer, and Spirits" forum put me in contact with some other brewers that, like me at the time, were relative newbies. The LHBS helped me refine things a bit and gave me the opportunity to really learn about ingredients. The club expanded my horizons, gave me the benefit of many great brewers' experience, exposed me to BJCP (which has been a big part of me becoming a better brewer), and exposed me to many beers that were not available in my local market at the time (and many that still are not). HBT has expanded my horizons even further and put me in touch with more experienced brewers and many innovative ones. HBT also helped reignite a passion that was on the verge of burning out.
So, I cannot point to one source. They've all mattered a great deal. I can't say I've learned much from podcasts or internet radio, though. They aren't talking to me.
Finally, the Brewing Gods (or Beer Gods) that I know aren't on any radio show.
TL