As an Electrical Engineering Editor, I read quite a bit. So, I decided to see what articles have been written about power supplies that are worth noting. Here is my list that I have compiled.
TDK Corporation has a great site for power supply information. Power Topics for Power Supply Users is a page to blog, learn or refresh your power skills. Scrolling down page, I saw the How to Avoid Being Ripped Off When Buying Power Supplies tip/topic located in the middle of the page. Initially posted on January 9, 2013, the best advice from this article was, “If it seems too good to be true, it probably isn’t (true).” What I truly enjoyed about reading this page were the insightful articles along with schematics for clarity.
Another site that has a great article on supplies is PC World. How to pick the best PC power supply had useful tips for choosing a supply. This article too, advised against buying cheap, generic power supplies.
VR-Zone has written an eight page article on how power supplies work. This article informed readers of the different types of power supplies that 
explained components while offering schematics. It was also good for fundamental learning of the construction of a power supply, or as an electrical component refresher.
Design World’s PowerSupplyTips.com also has great articles written about power supplies. With informative videos for the learning engineer, to articles written for the more advanced engineer, this site covers tips from the leading companies in the field of engineering.
One particular site that I receive weekly newsletters from. Solid State Technology is a source that runs the gamut on everything power. This site has a forum for blogs and webcasts, to press releases and to the most recent news in the electronics world.
XP Power is another site for good technical articles on power supplies. Although XP Power is a manufacturer, this company has articles for healthcare, technology, industrial, and engineering solutions.