Everything I've learned about photography, I learned by reading magazines and online resources. Here are some of my favorite online resources:
Simply the best place to buy new camera equipment. I've bought a couple of copies of a lens from Amazon just to see which was sharper, returned the less sharp of the two with no problem. Love Amazon.
The Digital Picture
The best way to do lens-to-lens comparisons.
Want to use an exotic lens or camera body, but don't want to shell out thousands of dollars? Rent them from LensRentals. Also, the owner's blogs about photography are super informative.
A self-taught commercial photographer who shares tips, insights, and behind-the-scenes details about his photo projects. I truly appreciate this guy.