Upload & Sell: Off
a second on the strobist site, no matter what brand you shoot with. there's a wealth of information there, and it's all free as air. (air is still free at the time of this writing.) additionally, there's a strobist group on flickr which is dedicated to exchanging technique information and discussing the strobist blog.
two things to mention about strobist.blogspot.com, though:
--david hobby (producer of strobist) comes at flash solutions from a manual-flash perspective.
--he shoots nikon, so when he does talk about automatic settings, it tends to be nikon-centric.