I grant you that this isn't my tutorial but rather a reference to tutorials. That being said, here ya go.
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I was poking around the SparkFun.com website and took a little time looking at what they have in the tutorials section. Quite a lot of it is illustrated well for beginners to novice. I thought I'd share this with our newer members but it's also a great refresher. It's may be a good reference for the commonly asked topics. Pull up resistors, current limiting resistors for LEDs, in depth coverage on serial terminal basics, voltage dividers, bluetooth basics, accelerometer basics, etc...it's all there!

Tutorials at Sparkfun