Found a neat blog will all kinds of topics on basic Microcontroller programming (as well as Linux and Mac hacking): http://www.downtowndougbrown.com/. The microcontroller-specific topics are here: http://www.downtowndougbrown.com/category/microcontroller-programming/. The author writes long-winded posts just like me! I can tell we’d be friends.
One of the things that caught my eye was the collection of posts on SPI and also the fact that a lot of the programming examples and techniques target AVR (which I’m trying to get into).